Rethinking causal assumptions about maternal BMI, gestational weight gain, and adverse pregnancy outcomes

BACKGROUND

The aim of this study was to evaluate commonly assumed causal relationships between body mass index (BMI), gestational weight gain (GWG), and adverse pregnancy outcomes, which have formed the basis of guidelines and interventions aimed at limiting GWG in women with overweight or obesity. We explored relationships between maternal BMI, total GWG (as a continuous variable and as 'excessive' GWG), and pregnancy outcomes (including infant birthweight measures and caesarean birth).

METHODS

Analysis of individual participant data (IPD) from the i-WIP (International Weight Management in Pregnancy) Collaboration, from randomised trials of diet and/or physical activity interventions during pregnancy reporting GWG and maternal and neonatal outcomes. Women randomised to the control arm of 20 eligible randomised trials (4370 of 8908 participants) from the i-WIP dataset of 36 randomised trials (total 12,240 women). The main research questions were to characterise the relationship between maternal BMI and (a) total GWG, (b) the risk of 'excessive' GWG (using the Institute of Medicine's guidelines), and (c) adverse pregnancy outcomes as mediated via GWG versus other pathways to determine the extent to which the observed effect of maternal BMI on pregnancy outcomes is mediated via GWG. We utilised generalised linear models and regression-based mediation analyses within an IPD meta-analysis framework.

RESULTS

Mean GWG decreased linearly as maternal BMI increased; however, the risk of 'excessive' GWG increased markedly at BMI category thresholds (i.e. between the normal and overweight BMI category threshold and between the overweight and obese BMI category threshold). Increasing maternal BMI was associated with increased risk of all pregnancy outcomes assessed; however, there was no evidence that this effect was mediated via effects on GWG.

CONCLUSIONS

There is evidence of a meaningful relationship between maternal BMI and GWG and between maternal BMI and adverse pregnancy outcomes. There is no evidence that the effect of maternal BMI on outcomes is via an effect on GWG. Our analyses also cast doubt on the existence of a relationship between 'excessive' GWG and adverse pregnancy outcomes. Our findings challenge the practice of actively managing GWG throughout pregnancy.

Effectiveness and implementation of lower-intensity weight management interventions delivered by the non-specialist workforce in postnatal women: a mixed-methods systematic review

Lower-intensity interventions delivered in primary and community care contacts could provide more equitable and scalable weight management support for postnatal women. This mixed-methods systematic review aimed to explore the effectiveness, implementation, and experiences of lower-intensity weight management support delivered by the non-specialist workforce. We included quantitative and qualitative studies of any design that evaluated a lower-intensity weight management intervention delivered by non-specialist workforce in women up to 5 years post-natal, and where intervention effectiveness (weight-related and/or behavioural outcomes), implementation and/or acceptability were reported. PRISMA guidelines were followed, and the review was prospectively registered on PROSPERO (CRD42022371828). Nine electronic databases were searched to identify literature published between database inception to January 2023. This was supplemented with grey literature searches and citation chaining for all included studies and related reviews (completed June 2023). Screening, data extraction and risk of bias assessments were performed in duplicate. Risk of bias was assessed using the Joanna Briggs Institute appraisal tools. Narrative methods were used to synthesise outcomes. Seven unique studies described in 11 reports were included from the Netherlands (n = 2), and the United Kingdom, Germany, Taiwan, Finland, and the United States (n = 1 each). All studies reported weight-related outcomes; four reported diet; four reported physical activity; four reported intervention implementation and process outcomes; and two reported intervention acceptability and experiences. The longest follow-up was 13-months postnatal. Interventions had mixed effects on weight-related outcomes: three studies reported greater weight reduction and/or lower postnatal weight retention in the intervention group, whereas four found no difference or mixed effects. Most studies reporting physical activity or diet outcomes showed no intervention effect, or mixed effects. Interventions were generally perceived as acceptable by women and care providers, although providers had concerns about translation into routine practice. The main limitations of the review were the limited volume of evidence available, and significant heterogeneity in interventions and outcome reporting which limited meaningful comparisons across studies. There is a need for more intervention studies, including process evaluations, with longer follow-up in the postnatal period to understand the role of primary and community care in supporting women's weight management. Public Health Wales was the primary funder of this review.

Effectiveness of nutrition counseling for pregnant women in low- and middle-income countries to improve maternal and infant behavioral, nutritional, and health outcomes: A systematic review

Background

Nutritional counseling, which includes two-way interactive education, has been hypothesized to improve the health and nutritional status of pregnant women, but little is known about the impact such practice of care might have on maternal and infant health and behavioral outcomes of pregnant women living in low income, low-middle income, and upper-middle-income countries (LMIC)s.

Objectives

We conducted a systematic review to appraise the effectiveness and impact on health equity of two-way nutritional counseling practices in LMICs on maternal and infant behavioral, nutritional, and health outcomes.

Search Methods

We conducted electronic searches for relevant studies on Medline, Embase, CINAHL, PsychInfo, and the Cochrane CENTRAL for randomized and non-randomized trials on the effectiveness of two-way interactive nutritional counseling among pregnant women from the date of database inception up to June 22, 2021. In addition, we searched references of included studies in systematic reviews, gray literature resources, and unpublished studies or reports that satisfied our eligibility criteria using a focused Google search.

Selection Criteria

We included randomized and non-randomized controlled studies (NRS), controlled before and after, and interrupted time series that assessed the effectiveness of two-way interactive nutrition counseling targeting pregnant women in LMICs.

Data Collection and Analysis

Data extraction and risk of bias were conducted in duplicate. The risk of bias (ROB) for randomized trials (RCT) was assessed according to the Cochrane Handbook of Systematic Reviews, and ROB for NRS was assessed using the Newcastle-Ottawa scale (NOS). RCT and NRS were meta-analyzed separately.

Main Results

Our search identified 6418 records and 52 studies met our inclusion criteria, but only 28 were used in the quantitative analysis. Twenty-eight studies were conducted in Asia, the most in Iran. Eight studies were conducted in Africa. Two-way interactive nutritional counseling during pregnancy may improve dietary caloric intake (mean difference [MD]: 81.65 calories, 95% confidence interval [CI], 15.37-147.93, three RCTs; I 2 = 42%; moderate certainty of evidence using GRADE assessment), may reduce hemorrhage (relative risk [RR]: 0.63; 95% CI, 0.25-1.54, two RCTs; I 2 = 40%; very low certainty of evidence using GRADE assessment), may improve protein (MD: 10.44 g, 95% CI, 1.83-19.05, two RCTs; I 2 = 95%; high certainty of evidence using GRADE assessment), fat intake (MD: 3.42 g, 95% CI, -0.20 to 7.04, two RCTs; I 2 = 0%; high certainty of evidence using GRADE assessment), and may improve gestational weight gain within recommendations (RR: 1.84; 95% CI, 1.10-3.09, three RCTs; I 2 = 69%). Nutrition counseling probably leads to the initiation of breastfeeding immediately after birth (RR: 1.72; 95% CI, 1.42-2.09, one RCT). There was little to no effect on reducing anemia (RR: 0.77; 95% CI, 0.50-1.20, three RCTs; I 2 = 67%; very low certainty of evidence using GRADE assessment) risk of stillbirths (RR: 0.81; 95% CI, 0.52-1.27, three RCTs; I 2 = 0%; moderate certainty of evidence using GRADE assessment) and risk of cesarean section delivery (RR: 0.96; 95% CI, 0.76-1.20, four RCTs; I 2 = 36%; moderate certainty of evidence using GRADE assessment).

Authors’ Conclusions

Our review highlights improvements in maternal behavioral and health outcomes through interactive nutrition counseling during pregnancy. However, we are uncertain about the effects of nutrition counseling due to the low certainty of evidence and a low number of studies for some key outcomes. Moreover, the effects on health equity remain unknown. More methodologically rigorous trials that focus on a precise selection of outcomes driven by the theory of change of nutrition counseling to improve maternal and infant behavioral and health outcomes and consider equity are required.

Medical and Psychological Aspects of Pregnancy in Women with Obesity and after Bariatric Surgery

Chronic diseases are potential risk factors for pregnancy duration and neonatal outcomes. This narrative review aimed to summarize the research results on the specifics of pregnancy in women with obesity and after bariatric surgery. PubMed and Google Scholar databases were searched. Systematic reviews, meta-analyses, clinical trials, and references to identified articles from the last ten years (2013-2023) were included. Ultimately, 107 literature items were qualified. It has been shown that women with obesity planning pregnancy should reduce their body weight because obesity is a risk factor for adverse obstetric and neonatal outcomes. Bariatric surgery effectively reduces excessive body weight and the health risks in women with obesity during pregnancy and their offspring. However, at least a year interval between surgery and conception is recommended. An interdisciplinary medical team should provide patient care during pregnancy with knowledge and skills related to people after bariatric surgery. Due to the increased risk of mental disorders, especially depression, it is necessary to constantly monitor the mental state of women and provide psychological support and education on a healthy lifestyle during pregnancy and the postpartum period.

Association between physical activity education and prescription during prenatal care and maternal and fetal health outcomes: a quasi-experimental study

BACKGROUND

Physical activity (PA) during pregnancy is associated with healthy gestational weight gain (GWG) and a reduced risk of developing gestational diabetes (GD), gestational hypertension (GHT) and fetal macrosomia. However, in Canada, less than 20% of pregnant women meet PA recommendations. This study assessed associations between an intervention including PA education by prenatal nurses and a PA prescription delivered by physicians and fetal and maternal outcomes.

METHODS

This is a quasi-experimental study. Two groups of women who received their prenatal care at the obstetrics clinic of a university hospital were created. In the first group, 394 pregnant women followed at the clinic received standard care. In the second group, 422 women followed at the clinic received standard care supplemented with education on the relevance of PA during pregnancy and a prescription for PA. Data for both study groups were obtained from the medical records of the mothers and their newborns. Logistic regressions were used to compare the odds of developing excessive GWG, GD, GHT, and fetal macrosomia between the two study groups.

RESULTS

The addition of PA education and PA prescription to prenatal care was associated with 29% lower odds of developing excessive GWG (adjusted odds ratios (OR) 0.71, 95% confidence intervals (CI) 0.51-0.99), 73% lower odds of developing GHT (0.27, 0.14-0.53), 44% lower odds of fetal macrosomia (> 4 kg) (0.56, 0.34-0.93), and 40% lower odds of being large for gestational age (0.60, 0.36-0.99). The intervention was not associated with a difference in odds of developing GD (0.48, 0.12-1.94).

CONCLUSIONS

The inclusion of education and prescription of PA as part of routine prenatal care was associated with improvements in maternal and fetal health outcomes, including significantly lower odds of GWG, GHT and macrosomia.

Key Components of Antenatal Lifestyle Interventions to Optimize Gestational Weight Gain: Secondary Analysis of a Systematic Review

Importance

Randomized clinical trials have found that antenatal lifestyle interventions optimize gestational weight gain (GWG) and pregnancy outcomes. However, key components of successful interventions for implementation have not been systematically identified.

Objective

To evaluate intervention components using the Template for Intervention Description and Replication (TIDieR) framework to inform implementation of antenatal lifestyle interventions in routine antenatal care.

Data Sources

Included studies were drawn from a recently published systematic review on the efficacy of antenatal lifestyle interventions for optimizing GWG. The Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, Health Technology Assessment Database, MEDLINE, and Embase were searched from January 1990 to May 2020.

Study Selection

Randomized clinical trials examining efficacy of antenatal lifestyle interventions in optimizing GWG were included.

Data Extraction and Synthesis

Random effects meta-analyses were used to evaluate the association of intervention characteristics with efficacy of antenatal lifestyle interventions in optimizing GWG. The results are reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline. Data extraction was performed by 2 independent reviewers.

Main Outcomes and Measures

The main outcome was mean GWG. Measures included characteristics of antenatal lifestyle interventions comprising domains related to theoretical framework, material, procedure, facilitator (allied health staff, medical staff, or researcher), delivery format (individual or group), mode, location, gestational age at commencement (<20 wk or ≥20 wk), number of sessions (low [1-5 sessions], moderate [6-20 sessions], and high [≥21 sessions]), duration (low [1-12 wk], moderate [13-20 wk], and high [≥21 wk]), tailoring, attrition, and adherence. For all mean differences (MDs), the reference group was the control group (ie, usual care).

Results

Overall, 99 studies with 34 546 pregnant individuals were included with differential effective intervention components found according to intervention type. Broadly, interventions delivered by an allied health professional were associated with a greater decrease in GWG compared with those delivered by other facilitators (MD, -1.36 kg; 95% CI, -1.71 to -1.02 kg; P < .001). Compared with corresponding subgroups, dietary interventions with an individual delivery format (MD, -3.91 kg; 95% CI -5.82 to -2.01 kg; P = .002) and moderate number of sessions (MD, -4.35 kg; 95% CI -5.80 to -2.89 kg; P < .001) were associated with the greatest decrease in GWG. Physical activity and mixed behavioral interventions had attenuated associations with GWG. These interventions may benefit from an earlier commencement and a longer duration for more effective optimization of GWG.

Conclusions and Relevance

These findings suggest that pragmatic research may be needed to test and evaluate effective intervention components to inform implementation of interventions in routine antenatal care for broad public health benefit.

A Comprehensive Review on Social Inequalities and Pregnancy Outcome-Identification of Relevant Pathways and Mechanisms

Scientific literature tends to support the idea that the pregnancy and health status of fetuses and newborns can be affected by maternal, parental, and contextual characteristics. In addition, a growing body of evidence reports that social determinants, measured at individual and/or aggregated level(s), play a crucial role in fetal and newborn health. Numerous studies have found social factors (including maternal age and education, marital status, pregnancy intention, and socioeconomic status) to be linked to poor birth outcomes. Several have also suggested that beyond individual and contextual social characteristics, living environment and conditions (or "neighborhood") emerge as important determinants in health inequalities, particularly for pregnant women. Using a comprehensive review, we present a conceptual framework based on the work of both the Commission on Social Determinants of Health and the World Health Organization (WHO), aimed at describing the various pathways through which social characteristics can affect both pregnancy and fetal health, with a focus on the structural social determinants (such as socioeconomic and political context) that influence social position, as well as on intermediary determinants. We also suggest that social position may influence more specific intermediary health determinants; individuals may, on the basis of their social position, experience differences in environmental exposure and vulnerability to health-compromising living conditions. Our model highlights the fact that adverse birth outcomes, which inevitably lead to health inequity, may, in turn, affect the individual social position. In order to address both the inequalities that begin in utero and the disparities observed at birth, it is important for interventions to target various unhealthy behaviors and psychosocial conditions in early pregnancy. Health policy must, then, support: (i) midwifery availability and accessibility and (ii) enhanced multidisciplinary support for deprived pregnant women.

Efficacious lifestyle interventions for appropriate gestational weight gain in women with overweight or obesity set in the health care system: a scoping review

Purpose: Health care systems offer opportunities to scale up interventions for appropriate gestational weight gain (GWG); however, GWG interventions in the health care setting remain largely unavailable to women with overweight or obesity. To inform the translation of efficacious lifestyle interventions to health care delivery systems, this scoping review aimed to systematically identify randomized controlled trials for appropriate GWG in women with overweight or obesity that were set in a health care system.Methods: A scoping review allows for the systematic synthesis of knowledge on an exploratory research question aimed at mapping key concepts (e.g. time, location, source, and evidence) and gaps in a specific area of study. The Colquhoun et al. (2014) framework to conducting scoping reviews was used to develop the research question, identify relevant studies, select studies, extract data, and synthesize data. Specifically, two reviewers searched publication databases for English-language articles published from January 2009 to May 2020 using specific keywords/MeSH terms.Results: Eight peer-reviewed journal articles were identified; six trials were based in Europe and two in the U.S. Only four included lifestyle interventions that were efficacious in reducing GWG. Three trials with efficacious interventions were among women with obesity only and encouraged them to gain at or below the lower limit for total GWG (i.e. ≤5 kg) of the Institute of Medicine (IOM) guidelines. The fourth was among women with overweight or obesity and encouraged women to gain within the IOM guidelines with a telehealth behavioral intervention. Efficacious interventions were initiated in the first half of pregnancy and included frequent contact delivered through multiple modalities (i.e. in-person visits, telephone calls, text messages, email) by trained intervention staff (i.e. dietitian, lifestyle coach, and/or physiotherapist). Only one efficacious intervention trial briefly mentioned theoretical components for health promotion (e.g. self-monitoring); likewise, only one included cost-effectiveness analyses.Conclusions: This review systematically identified randomized controlled trials of efficacious lifestyle interventions (i.e. consisting of diet and physical activity components) for appropriate GWG in women with overweight or obesity that were set in the health care system and delivered by non-clinicians. Translation efforts could draw upon aspects of the efficacious lifestyle interventions described in this review. Future studies should examine theory-based telehealth interventions and cost-effectiveness.

Implementation of Antenatal Lifestyle Interventions Into Routine Care: Secondary Analysis of a Systematic Review

IMPORTANCE

Lifestyle interventions in pregnancy optimize gestational weight gain and improve pregnancy outcomes, with implementation recommended by the US Preventive Services Task Force. Yet, implementation research taking these efficacy trials into pragmatic translation remains limited.

OBJECTIVE

To evaluate success factors for implementing pregnancy lifestyle interventions into antenatal care settings in a meta-analysis, using the penetration, implementation, participation, and effectiveness (PIPE) impact metric.

DATA SOURCES

Data from a previous systematic review that searched across 9 databases, including MEDLINE, Embase, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, and Health Technology Assessment Database, were obtained, in 2 stages, up to May 6, 2020.

STUDY SELECTION

Randomized clinical trials reporting gestational weight gain in singleton pregnancies.

DATA EXTRACTION AND SYNTHESIS

The association of penetration, implementation, and participation with effectiveness of antenatal lifestyle interventions in optimizing gestational weight gain was estimated using random-effects meta-analyses. The Cochrane risk of bias tool, version 1.0, was used to assess risk of bias.

MAIN OUTCOMES AND MEASURES

Penetration (reach), implementation (fidelity), participation, and effectiveness of randomized clinical trials of lifestyle interventions in pregnancy.

RESULTS

Ninety-nine studies with 34 546 participants were included. Only 14 studies reported penetration of target populations. Overall, 38 studies (38.4%) had moderate fidelity, 25 (25.2%) had high fidelity, and 36 (36.4%) had unclear fidelity. Participation was reported in 84 studies (84.8%). Lifestyle interventions were associated with reducing gestational weight gain by 1.15 kg (95% CI, -1.40 to -0.91 kg).

CONCLUSIONS AND RELEVANCE

The findings of this systematic review and meta-analysis suggest that, despite the large body of evidence on efficacy of lifestyle interventions during pregnancy in optimizing gestational weight gain, little guidance is available to inform implementation of this evidence into practice. There is a need to better elucidate implementation outcomes in trial design alongside pragmatic implementation research to improve the health of women who are pregnant and the next generation.

Efficacy of behavioral interventions in managing gestational weight gain (GWG): A component network meta-analysis

OBJECTIVE

To identify the most effective behavioral components within lifestyle interventions to optimize gestational weight gain (GWG) to inform guidelines, policy and translation into healthcare.

METHODS

Behavioral components were identified from study level data of randomized antenatal lifestyle interventions using a behavioral taxonomy framework and analyzed using component network meta-analysis (NMA). The NMA ranked behavioral combinations hierarchically by efficacy of optimizing GWG. Direct and estimated indirect comparisons between study arms (i.e., control and intervention) and between different component combinations were estimated to evaluate component combinations associated with greater efficacy.

RESULTS

Overall, 32 studies with 11,066 participants were included. Each intervention contained between 3 and 7 behavioral components with 26 different behavioral combinations identified. The majority (n = 24) of combinations were associated with optimizing GWG, with standard mean differences (SMD) ranging from -1.01 kg (95% CI -1.64 to -0.37) and -0.07 kg (-0.38 to 0.24), compared with controls. The behavioral cluster identified as most effective, included components of goals, feedback and monitoring, natural consequences, comparison of outcomes, and shaping knowledge (SMD -1.01 kg [95% CI -1.64 to -0.37]).

CONCLUSION

Findings support the application of goal setting, feedback and monitoring, natural consequences, comparison of outcomes, and shaping knowledge as essential, core components within lifestyle interventions to optimize gestational weight gain.

Impact of missing outcome data in meta-analyses of lifestyle interventions during pregnancy to reduce postpartum weight retention: An overview of systematic reviews with meta-analyses and additional sensitivity analyses

High risk of bias associated with missing outcome data (MOD) in meta-analyses (MAs) of the effects of lifestyle interventions during pregnancy on postpartum weight retention (PPWR) casts doubt on whether such interventions can be relied upon as truly effective. This systematic overview of three MAs (19 RCTs), each with high MOD rates in the subset of RCTs included, examined how MOD were addressed in the estimation of summary intervention effects. All MAs reported beneficial and statistically significant intervention effects estimated based on complete case analyses, deemed valid if MOD was missing at random (MAR). Therefore, we conducted sensitivity analyses using pattern mixture models and informative missingness parameters (describing how the outcome in the missing participants may be related to the outcome in the completers), to ascertain the robustness of the estimates to reasonable deviations from the MAR assumption. In plausible scenarios where the response in intervention group participants with versus without MOD was worse (by just 0.5 kg), effect estimates were attenuated in all MAs and no longer statistically significant in two MAs. Statistical significance was retained when all 19 RCTs identified across MAs were examined together in a broader meta-analysis: -0.63 kg (95%CI -0.17, -0.08), but the clinical relevancy of effects of this magnitude remains unclear.

Counseling and Behavioral Interventions for Healthy Weight and Weight Gain in Pregnancy: Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Counseling and active behavioral interventions to limit excess gestational weight gain (GWG) during pregnancy may improve health outcomes for women and infants. The 2009 National Academy of Medicine (NAM; formerly the Institute of Medicine) recommendations for healthy GWG vary according to prepregnancy weight category.

OBJECTIVE

To review and synthesize the evidence on benefits and harms of behavioral interventions to promote healthy weight gain during pregnancy to inform the US Preventive Services Task Force recommendation.

DATA SOURCES

Ovid MEDLINE and the Cochrane Library to March 2020, with surveillance through February 2021.

STUDY SELECTION

Randomized clinical trials and nonrandomized controlled intervention studies focused on diet, exercise, and/or behavioral counseling interventions on GWG.

DATA EXTRACTION AND SYNTHESIS

Independent data abstraction and study quality rating with dual review.

MAIN OUTCOMES AND MEASURES

Gestational weight-related outcomes; maternal and infant morbidity and mortality; harms.

RESULTS

Sixty-eight studies (N = 25 789) were included. Sixty-seven studies evaluated interventions during pregnancy, and 1 evaluated an intervention prior to pregnancy. GWG interventions were associated with reductions in risk of gestational diabetes (43 trials, n = 19 752; relative risk [RR], 0.87 [95% CI, 0.79 to 0.95]; absolute risk difference [ARD], -1.6%) and emergency cesarean delivery (14 trials, n = 7520; RR, 0.85 [95% CI, 0.74 to 0.96]; ARD, -2.4%). There was no significant association between GWG interventions and risk of gestational hypertension, cesarean delivery, or preeclampsia. GWG interventions were associated with decreased risk of macrosomia (25 trials, n = 13 990; RR, 0.77 [95% CI, 0.65 to 0.92]; ARD, -1.9%) and large for gestational age (26 trials, n = 13 000; RR, 0.89 [95% CI, 0.80 to 0.99]; ARD, -1.3%) but were not associated with preterm birth. Intervention participants experienced reduced weight gain across all prepregnancy weight categories (55 trials, n = 20 090; pooled mean difference, -1.02 kg [95% CI, -1.30 to -0.75]) and demonstrated lower likelihood of GWG in excess of NAM recommendations (39 trials, n = 14 271; RR, 0.83 [95% CI, 0.77 to 0.89]; ARD, -7.6%). GWG interventions were associated with reduced postpartum weight retention at 12 months (10 trials, n = 3957; mean difference, -0.63 kg [95% CI, -1.44 to -0.01]). Data on harms were limited.

CONCLUSIONS AND RELEVANCE

Counseling and active behavioral interventions to limit GWG were associated with decreased risk of gestational diabetes, emergency cesarean delivery, macrosomia, and large for gestational age. GWG interventions were also associated with modest reductions in mean GWG and decreased likelihood of exceeding NAM recommendations for GWG.

An integrative review of interventions for limiting gestational weight gain in pregnant women who are overweight or obese

PROBLEM

Excessive gestational weight gain in women who are overweight or obese puts them at risk of poor short- and long-term outcomes for maternal and neonatal health. Several interventions have been trialled to encourage women who are overweight or obese to limit gestational weight gain during pregnancy.

AIM

The aim of this review was to analyse the evidence on interventions to limit gestational weight gain in pregnant women who are overweight or obese.

METHOD

An integrative review guided by the Joanna Briggs Institute approach was conducted. An unlabeled search query of pregnancy, weight, and obesity was conducted in Medline, Scopus and CINAHL, limited to English language, 2010-2020 publications, and primary research on humans. Unlabeled search query of "((pregnancy outcome) OR (prenatal care) OR (pregnancy complications)) AND ((weight loss) OR (weight gain) OR (weight management)) AND (obesity) was used. Additional 9 records were identified through reference lists. Following a critical appraisal, 21 primary research articles were included in this review. A thematic synthesis was undertaken.

FINDINGS

Four major themes were identified. These are (1) mixed findings of lifestyle interventions for weight management, (2) ineffectiveness of probiotics or metformin for weight management, (3) psycho-behavioural interventions for weight management, and (4) midwifery role as an integral component in multidisciplinary intervention for weight management.

CONCLUSION

The literature suggests a need for longer duration of behavioural lifestyle intervention sessions led by the same midwife trained in motivational interviewing to limit weight gain in pregnant women who are overweight or obese.

Effectiveness of a normative nutrition intervention in Chilean pregnant women on maternal and neonatal outcomes: the CHiMINCs study

BACKGROUND

Some nutritional interventions have shown their efficacy in reducing gestational weight gain (GWG); however, their applicability in routine care is limited.

OBJECTIVE

We assessed the effectiveness of a low-intensity and high-coverage nutritional intervention on maternal and offspring outcomes; the intervention enhanced existing nutritional health care standards and practices at the primary health care level in Chile.

METHODS

This study was a cluster-randomized controlled trial of 12 primary health care centers (PHCCs) from Santiago, Chile. PHCCs were randomly allocated to either nutritional intervention [intervention group (IG), n = 5] or routine care [control group (CG), n = 7]. A total of 4631 pregnant women were recruited (IG, n = 2565; and CG, n = 2066). Primary outcomes were adequate GWG and glycemic control in mothers and birth weight, birth length, macrosomia, and large for gestational age in neonates. The intervention consisted of 4 key actions: training of health care professionals on nutritional recommendations, counseling of pregnant women on diet and physical activity recommendations, offering a physical activity program implemented in the participating PHCCs, and adequate referral to dietitians. Women randomly assigned to the CG received routine antenatal care.

RESULTS

At baseline, the mean age was 26.1 y; 45% of women were primipara and 24% were obese. No differences were found in the percentage of women achieving adequate GWG (IG: 30.3%, compared with CG: 31.3%; OR: 0.94; 95% CI: 0.81, 1.09), but women in the IG had lower GWG than those in the CG (11.3 compared with 11.9 kg; mean difference: -0.63 kg; 95% CI: -1.19, -0.08). Effects of the intervention were significantly higher in women with obesity at the begining of pregnancy (mean difference: -1.24 kg; 95% CI: -2.18, -0.30; P for interaction < 0.05). No differences were found between groups regarding maternal glycemic control or neonatal outcomes.

CONCLUSIONS

Our findings demonstrate that a low-intensity, high-coverage intervention delivered through the Chilean public health care system under standard operating conditions reduces GWG and has the potential for successful scale-up. This trial was registered at clinicaltrials.gov as NCT01916603.

A lifestyle intervention during pregnancy to reduce obesity in early childhood: the study protocol of ADEBAR - a randomized controlled trial

BACKGROUND

The prevalence of obesity in childhood is increasing worldwide and may be affected by genetic factors and the lifestyle (exercise, nutrition behavior) of expectant parents. Lifestyle factors affect adipokines, namely leptin, resistin, and adiponectin as well as cytokines such as tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), which are involved in the regulation of maternal metabolic homeostasis, glucose metabolism, and the development of insulin resistance, metabolic syndrome, gestational diabetes mellitus, and hypertension. However, studies focusing on the effect of exercise or a combination of parental exercise and nutrition on the above-mentioned markers in newborns (venous cord blood) and especially on the long-term development of infants' weight gain are lacking. The study will investigate the effects of a multimodal intervention (regular exercise, diet) on parental and childhood adipocytokines (leptin, resistin, adiponectin, TNF-α, IL-6, BDNF). The effect of a lifestyle-related change in "fetal environmental conditions" on the long-term weight development of the child up to the age of two will also be assessed.

METHODS/DESIGN

A randomized multi-center controlled trial will be conducted in Germany, comparing supervised aerobic and resistance training 2x/week (13th to 36th weeks of gestation) and nutritional counseling (6th to 36th weeks of gestation) during pregnancy with usual care. Thirty women (pre-pregnancy Body Mass Index ≥25 kg/m2, 6th-10th week of gestation) will be included in each group. Maternal anthropometric and physical measurements as well as blood sampling will occur at the 6th-10th, 13th-14th, 21st-24th, and 36th week of gestation, at delivery as well as 8 weeks and 24 months postpartum. Neonatal measurements and umbilical blood sampling will be performed at birth. Maternal and infants' weight development will be assessed every 6 months till 24 months postpartum. A difference in childhood BMI of 1 kg/m2 at the age of two years between both groups will be assumed. A power size of 80% using a significance level of 0.05 and an effect size of 1.0 is presumed.

DISCUSSION

A better understanding of how lifestyle-related changes in the fetal environment might influence infants' outcome after two years of life could have a profound impact on the prevention and development of infants' obesity.

TRIAL REGISTRATION

The trial is registered at the German Clinical Trial Register (DRKS00007702); Registered on 10th of August 2016; retrospectively registered https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00007702.

The effectiveness of healthy lifestyle interventions on weight gain in overweight pregnant women: A cluster-randomized controlled trial

Aim

Interventions based on adopting a healthy lifestyle have been less successful. The aim of this study was to investigate the effectiveness of healthy lifestyle interventions on weight gain in overweight pregnant women.

Design

A cluster randomized controlled trial.

Methods

Health centres were selected by simple random sampling; then, 66 overweight pregnant women were enrolled by convenience sampling and divided into intervention and comparison groups. Intervention group received individual nutritional counselling and physical activity training. The data were collected in several stages with the demographic and obstetric questionnaire, maternal weight record, food frequency and international physical activity questionnaire.

Results

Pregnancy weight gain‐4.75(CI 95%: −4.02, −5.48) was significantly lower in the intervention group (p < .001). Comparing between groups with adjustment for baseline values indicated that there was a statistically significant difference in terms of total calorie 95.46 (CI 95%: −22.37, 213.30), carbohydrate 23.45 (CI 95%: 2.12, 44.78), protein −7.16 (CI 95%: −12.85, −1.47) and fat 8.82 (CI 95%: 2.21, 15.67) intake. Despite the higher level of physical activity in the intervention group, there was no statistically significant difference between the two groups.

Conclusion

Counselling interventions for healthy living during pregnancy can lead to controlling weight gain, improving dietary habits and increasing the physical activity in overweight pregnant women.

Effect of counselling with men on perceived stress and social support of their pregnant wives

BACKGROUND

Given the important role of spouses during pregnancy, this study aimed to determine the effect of counseling with men on stress and social support of their women (primary outcomes), anxiety, depression, weight gain, newborns' anthropometric indicators, frequency of cesarean section and preterm delivery (secondary outcomes).

METHODS

102 pregnant women were randomly assigned to two groups of counseling and control. Four sessions of counseling were held for the spouses of intervention group. Perceived Personal Resource Questionnaire-85-Part2, Perceived Stress Scale, Edinburgh's Postpartum Depression Scale, and Spielberger's State and Trait Anxiety Inventory were completed before and four weeks after intervention. The participants were followed up until delivery, and newborns' anthropometric indicators, delivery type, and preterm delivery were recorded.

RESULTS

The mean score of social support increased significantly 4 weeks after intervention in the counseling group compared to the control group (MD:12.7; 95%CI: 18.5 to 6.9). There was no significant difference between groups in the mean score of stress, anxiety, depression, and weight gain during pregnancy at four weeks after intervention and also frequency of cesarean delivery, preterm delivery, and anthropometric indicators of newborns (p>0.05).

CONCLUSIONS

Counseling with fathers can be recommended as an effective intervention to increase social support of pregnant women.

TRIAL REGISTRATION

IRCT2017042910324N38. Registered 25 June 2017, http://en.irct.ir/trial/10813.

Lifestyle information and access to a commercial weight management group to promote maternal postnatal weight management and positive lifestyle behaviour: the SWAN feasibility RCT

Background

Increasing numbers of UK women have overweight or obese body mass index scores when they become pregnant, or gain excessive weight in pregnancy, increasing their risk of adverse outcomes. Failure to manage postnatal weight is linked to smoking, non-healthy dietary choices, lack of regular exercise and poorer longer-term health. Women living in areas of higher social deprivation are more likely to experience weight management problems postnatally.

Objectives

The objectives were to assess the feasibility of conducting a definitive randomised controlled trial to determine the clinical effectiveness and cost-effectiveness of lifestyle information and access to a commercial weight management group focusing on self-monitoring, goal-setting and motivation to achieve dietary change commencing 8–16 weeks postnatally to achieve and maintain weight management and positive lifestyle behaviour.

Design

The design was a randomised two-arm feasibility trial with a nested mixed-methods process evaluation.

Setting

The setting was a single centre in an inner city setting in the south of England.

Participants

Participants were women with body mass index scores of > 25 kg/m2 at antenatal ‘booking’ and women with normal body mass index scores (18.0–24.9 kg/m2) at antenatal booking who developed excessive gestational weight gain as assessed at 36 weeks’ gestation.

Main outcome measures

Recruitment, retention, acceptability of trial processes and identification of relevant economic data were the feasibility objectives. The proposed primary outcome was difference between groups in weight at 12 months postnatally, expressed as percentage weight change and weight loss from antenatal booking. Other proposed outcomes included assessment of diet, physical activity, smoking, alcohol consumption, body image, maternal esteem, mental health, infant feeding and NHS costs.

Results

Most objectives were achieved. A total of 193 women were recruited, 98 allocated to the intervention arm and 95 to the control arm. High follow-up rates (> 80%) were achieved to 12 months. There was an 8.8% difference in weight loss at 12 months between women allocated to the intervention arm and women allocated to the control arm (13.0% vs. 4.2%, respectively; p = 0.062); 47% of women in the intervention arm attended at least one weight management session, with low risk of contamination between arms. The greatest benefit was among women who attended ≥ 10 sessions. Barriers to attending sessions included capability, opportunity and motivation issues. Data collection tools were appropriate to support economic evaluation in a definitive trial, and economic modelling is feasible to quantify resource impacts and outcomes not directly measurable within a trial.

Limitations

The trial recruited from only one site. It was not possible to recruit women with normal body mass index scores who developed excessive pregnancy weight gain.

Conclusions

It was feasible to recruit and retain women with overweight or obese body mass index scores at antenatal booking to a trial comparing postnatal weight management plus standard care with standard care only and collect relevant data to assess outcomes. Approaches to recruit women with normal body mass index scores who gain excessive gestational weight need to be considered. Commercial weight management groups could support women’s weight management as assessed at 12 months postnatally, with probable greater benefit from attending ≥ 10 sessions. Process evaluation findings highlighted the importance of providing more information about the intervention on trial allocation, extended duration of time to commence sessions following birth and extended number of sessions offered to enhance uptake and retention. Results support the conduct of a future randomised controlled trial.

Trial registration

Current Controlled Trials ISRCTN39186148.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 8, No. 9. See the NIHR Journals Library website for further project information.

Variations in long-term outcome reporting among offspring followed up after lifestyle interventions in pregnancy: a systematic review

Background Mothers and their offspring may benefit from lifestyle interventions during pregnancy. We systematically reviewed the literature to map and evaluate the quality of long-term offspring outcomes in follow-up cohorts of randomised controlled trials (RCTs). Methods We searched MEDLINE, EMBASE, CINAHL, Database of Abstracts of Reviews of Effects and Cochrane Central (until March 2019) for all RCTs evaluating any lifestyle (diet or exercise) intervention during pregnancy and their follow-up cohorts. Two reviews evaluated the extracted outcomes using two standardised assessment tools, one for quality of reporting (score range 0-6) and another for the variation in outcome selection. We extracted data in duplicate and reported using natural frequencies, medians, ranges, means and standard deviation (SD). Results We captured 30 long-term offspring outcomes reported in six articles (four studies). Offspring anthropometric measurements were the most commonly reported outcomes. There was a large variation in the measurement tools used. The mean overall quality score for outcome reporting was 3.33 (SD 1.24), with poor reporting of secondary outcomes and limited justification for the choice of the reported outcomes. Most studies showed selective reporting for both their primary and secondary outcomes. Conclusion The quality of reporting for long-term offspring outcomes following lifestyle interventions in pregnancy is varied with evidence of selective outcome reporting. Developing a core outcome set will help to reduce the variations in outcome reporting to optimise future research.

A Randomised Trial to Optimise Gestational Weight Gain and Improve Maternal and Infant Health Outcomes through Antenatal Dietary, Lifestyle and Exercise Advice: The OPTIMISE Randomised Trial

There are well-recognised associations between excessive gestational weight gain (GWG) and adverse pregnancy outcomes, including an increased risk of pre-eclampsia, gestational diabetes and caesarean birth. The aim of the OPTIMISE randomised trial was to evaluate the effect of dietary and exercise advice among pregnant women of normal body mass index (BMI), on pregnancy and birth outcomes. The trial was conducted in Adelaide, South Australia. Pregnant women with a body mass index in the healthy weight range (18.5–24.9 kg/m²) were enrolled in a randomised controlled trial of a dietary and lifestyle intervention versus standard antenatal care. The dietitian-led dietary and lifestyle intervention over the course of pregnancy was based on the Australian Guide to Healthy Eating. Baseline characteristics of women in the two treatment groups were similar. There was no statistically significant difference in the proportion of infants with birth weight above 4.0 kg between the Lifestyle Advice and Standard Care groups (24/316 (7.59%) Lifestyle Advice versus 26/313 (8.31%) Standard Care; adjusted risk ratio (aRR) 0.91; 95% confidence interval (CI) 0.54 to 1.55; p = 0.732). Despite improvements in maternal diet quality, no significant differences between the treatment groups were observed for total GWG, or other pregnancy and birth outcomes.

SLK Triple Therapy Improves Maternal and Fetal Status and Promotes Postpartum Pelvic Floor Function in Chinese Primiparous Women

Background

During pregnancy, appropriate physical activity plays critical roles in maternal and fetal health. This study investigated the effects of Sophrology childbirth-Kegel-Lamaze respiratory training (SLK triple therapy) on maternal and newborn health, pelvic floor function, and quality of life.

Material/Methods

Single-pregnant primiparous women involved in this study were divided into the control group (n=120) and the SLK triple therapy group (n=120). SLK triple therapy was taught to and practiced by the women in the SLK triple therapy group. Data on delivery mode (natural delivery or cesarean section), postpartum complications (postpartum urinary incontinence, postpartum hemorrhage), and birth process were recorded. Apgar scores and body weight of newborns were evaluated. Pelvic floor function, postpartum emotion, and sexual functions were assessed.

Results

Women in the SLK triple therapy group had significantly better natural delivery rate compared to the control group (p<0.05). SLK triple therapy significantly decreased the postpartum urinary incontinence rate and reduced the postpartum hemorrhage rate compared to the control group (p<0.05). Birth process and postpartum hemorrhage volume in the SLK triple therapy group were also significantly lower compared to the control group (p<0.05). Apgar scores were significantly lower and body weights were significantly higher in the SLK triple therapy group compared to the control group (p<0.05). SLK triple therapy significantly improved pelvic floor function compared to the control group (p<0.05). SLK triple therapy significantly decreased SDS scores and enhanced FSFI scores compared to the control group (p<0.05).

Conclusions

SLK triple therapy improved maternal and fetal health by improving pregnancy outcomes, promoting postpartum pelvic floor function, reducing the incidence of depression, and enhancing sexual function. Therefore, SLK triple therapy has great utility in treating primiparous women.

Towards Prepared mums (TOP-mums) for a healthy start, a lifestyle intervention for women with overweight and a child wish: study protocol for a randomised controlled trial in the Netherlands

INTRODUCTION

Periconception obesity is associated with a higher risk for adverse perinatal outcomes such as gestational diabetes mellitus, preeclampsia, large for gestational age, operative delivery and preterm birth. Lifestyle interventions during pregnancy have resulted in insufficient effects on reducing these perinatal complications. A few reasons for this disappointing effect can be suggested: (1) the time period during pregnancy for improvement of developmental circumstances is too short; (2) the periconception period in which complications originate is not included; and (3) lifestyle interventions may not have been sufficiently multidisciplinary and customised. A preconception lifestyle intervention might be more effective to reduce perinatal complications. Therefore, the aim of the Towards Prepared mums study is to evaluate the effect of a lifestyle intervention starting prior to conception on lifestyle behaviour change.

METHODS AND ANALYSIS

This protocol outlines a non-blinded, randomised controlled trial. One hundred and twelve women (18-40 years of age) with overweight or obesity (body mass index≥25.0 kg/m²) who plan to conceive within 1 year will be randomised to either the intervention or care as usual group. The intervention group will receive a multidisciplinary, customised lifestyle intervention stimulating physical activity, a healthy diet and smoking cessation, if applicable. The lifestyle intervention and monitoring will take place until 12 months postpartum. The primary outcome is difference in weight in kg from baseline to 6 weeks postpartum. Secondary outcomes are gestational weight gain, postpartum weight retention, smoking cessation, dietary and physical activity habits. Furthermore, exploratory outcomes include body composition, cardiometabolic alterations, time to pregnancy, need for assisted reproductive technologies, perinatal complications of mother and child, and lung function of the child. Vaginal and oral swabs, samples of faeces, breast milk, placenta and cord blood will be stored for evaluation of microbial flora, epigenetic markers and breast milk composition. Furthermore, a cost-effectiveness analysis will take place.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Medical Ethical Committee of Maastricht University Medical Centre+ (NL52452.068.15/METC152026). Knowledge derived from this study will be made available by publications in international peer-reviewed scientific journals and will be presented at (inter)national scientific conferences. A dissemination plan for regional and national implementation of the intervention is developed.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT02703753.

Walking for health during pregnancy: A literature review and considerations for future research

Walking is the most commonly chosen type of physical activity (PA) during pregnancy and provides several health benefits to both mother and child. National initiatives have promoted the importance of walking in general, but little emphasis is directed toward pregnant women, the majority of whom are insufficiently active. Pregnant women face a variety of dynamic barriers to a physically active lifestyle, some of which are more commonly experienced during specific times throughout the pregnancy experience. Walking is unique in that it appears resistant to a number of these barriers that limit other types of PA participation, and it can be meaningfully integrated into some transportation and occupational activities when leisure-time options are unavailable. Preliminary intervention work suggests that walking programs can be effectively adopted into a typical pregnancy lifestyle. However, a great deal of work remains to administer successful pregnancy walking interventions, including developing and using validated methods of PA and walking assessment. This narrative review discusses the unique advantages of walking during pregnancy, provides recommendations for future intervention work, and outlines the need for pregnancy-focused community walking initiatives. Standard search procedures were followed to determine sources from the literature specific to walking during pregnancy for use in each section of this review.

Impact of maternal education on response to lifestyle interventions to reduce gestational weight gain: individual participant data meta-analysis

OBJECTIVES

To identify if maternal educational attainment is a prognostic factor for gestational weight gain (GWG), and to determine the differential effects of lifestyle interventions (diet based, physical activity based or mixed approach) on GWG, stratified by educational attainment.

DESIGN

Individual participant data meta-analysis using the previously established International Weight Management in Pregnancy (i-WIP) Collaborative Group database (https://iwipgroup.wixsite.com/collaboration). Preferred Reporting Items for Systematic reviews and Meta-Analysis of Individual Participant Data Statement guidelines were followed.

DATA SOURCES

Major electronic databases, from inception to February 2017.

ELIGIBILITY CRITERIA

Randomised controlled trials on diet and physical activity-based interventions in pregnancy. Maternal educational attainment was required for inclusion and was categorised as higher education (≥tertiary) or lower education (≤secondary).

RISK OF BIAS

Cochrane risk of bias tool was used.

DATA SYNTHESIS

Principle measures of effect were OR and regression coefficient.

RESULTS

Of the 36 randomised controlled trials in the i-WIP database, 21 trials and 5183 pregnant women were included. Women with lower educational attainment had an increased risk of excessive (OR 1.182; 95% CI 1.008 to 1.385, p =0.039) and inadequate weight gain (OR 1.284; 95% CI 1.045 to 1.577, p =0.017). Among women with lower education, diet basedinterventions reduced risk of excessive weight gain (OR 0.515; 95% CI 0.339 to 0.785, p = 0.002) and inadequate weight gain (OR 0.504; 95% CI 0.288 to 0.884, p=0.017), and reduced kg/week gain (B -0.055; 95% CI -0.098 to -0.012, p=0.012). Mixed interventions reduced risk of excessive weight gain for women with lower education (OR 0.735; 95% CI 0.561 to 0.963, p=0.026). Among women with high education, diet based interventions reduced risk of excessive weight gain (OR 0.609; 95% CI 0.437 to 0.849, p=0.003), and mixed interventions reduced kg/week gain (B -0.053; 95% CI -0.069 to -0.037,p<0.001). Physical activity based interventions did not impact GWG when stratified by education.

CONCLUSIONS

Pregnant women with lower education are at an increased risk of excessive and inadequate GWG. Diet based interventions seem the most appropriate choice for these women, and additional support through mixed interventions may also be beneficial.

One-year postpartum anthropometric outcomes in mothers and children in the LIFE-Moms lifestyle intervention clinical trials

BACKGROUND/OBJECTIVES

Excess gestational weight gain (GWG) is a risk factor for maternal postpartum weight retention and excessive neonatal adiposity, especially in women with overweight or obesity. Whether lifestyle interventions to reduce excess GWG also reduce 12-month maternal postpartum weight retention and infant weight-for-length z score is unknown. Randomized controlled trials from the LIFE-Moms consortium investigated lifestyle interventions that began in pregnancy and tested whether there was benefit through 12 months on maternal postpartum weight retention (i.e., the difference in weight from early pregnancy to 12 months) and infant-weight-for-length z scores.

SUBJECTS/METHODS

In LIFE-Moms, women (N = 1150; 14.1 weeks gestation at enrollment) with overweight or obesity were randomized within each of seven trials to lifestyle intervention or standard care. Individual participant data were combined and analyzed using generalized linear mixed models with trial entered as a random effect. The 12-month assessment was completed by 83% (959/1150) of women and 84% (961/1150) of infants.

RESULTS

Compared with standard care, lifestyle intervention reduced postpartum weight retention (2.2 ± 7.0 vs. 0.7 ± 6.2 kg, respectively; difference of -1.6 kg (95% CI -2.5, -0.7; p = 0.0003); the intervention effect was mediated by reduction in excess GWG, which explained 22% of the effect on postpartum weight retention. Lifestyle intervention also significantly increased the odds (OR = 1.68 (95% CI, 1.26, 2.24)) and percentage of mothers (48.2% vs. 36.2%) at or below baseline weight at 12 months postpartum (yes/no) compared with standard care. There was no statistically significant treatment group effect on infant anthropometric outcomes at 12 months.

CONCLUSIONS

Compared with standard care, lifestyle interventions initiated in pregnancy and focused on healthy eating, increased physical activity, and other behavioral strategies resulted in significantly less weight retention but similar infant anthropometric outcomes at 12 months postpartum in a large, diverse US population of women with overweight and obesity.

Effects of a Lifestyle Intervention in Routine Care on Short- and Long-Term Maternal Weight Retention and Breastfeeding Behavior-12 Months Follow-up of the Cluster-Randomized GeliS Trial

Postpartum weight retention (PPWR) is associated with an increased risk for maternal obesity and is discussed to be influenced by breastfeeding. The objective was to evaluate the effect of a lifestyle intervention delivered three times during pregnancy and once in the postpartum period on PPWR and on maternal breastfeeding behavior. In total, 1998 participants of the cluster-randomized “healthy living in pregnancy” (GeliS) trial were followed up until the 12th month postpartum (T2_pp). Data were collected using maternity records and questionnaires. Data on breastfeeding behavior were collected at T2_pp. At T2_pp, mean PPWR was lower in women receiving counseling (IV) compared to the control group (C) (−0.2 ± 4.8 kg vs. 0.6 ± 5.2 kg), but there was no significant evidence of between-group differences (adjusted p = 0.123). In the IV, women lost more weight from delivery until T2_pp compared to the C (adjusted p = 0.008) and showed a slightly higher rate of exclusive breastfeeding (IV: 87.4%; C: 84.4%; adjusted p < 0.001). In conclusion, we found evidence for slight improvements of maternal postpartum weight characteristics and the rate of exclusive breastfeeding in women receiving a lifestyle intervention embedded in routine care, although the clinical meaning of these findings is unclear.

The Behavioral Wellness in Pregnancy study: a randomized controlled trial of a multi-component intervention to promote appropriate weight gain

BACKGROUND

Adequate weight gain during pregnancy is important to both maternal and fetal outcomes. To date, randomized controlled trials have not been effective at increasing the proportion of women meeting gestational weight-gain guidelines.

OBJECTIVES

The aim of this study was to determine whether a multi-component behavioral intervention with a Registered Dietitian Nutritionist significantly improves the proportion of women who adhere to the 2009 Institute of Medicine weight-gain guidelines.

METHODS

Participants were randomly assigned to usual care (UC; n = 24) or intervention (n = 23) between 8 and 14 weeks of gestation. The intervention included a minimum of 6 one-on-one counseling sessions over ∼30 wk focusing on healthy diet and physical activity (PA) goals. In addition to the face-to-face visits, weekly communication via email supported healthy eating, PA, and appropriate weight gain. Gestational weight gain, PA, and diet were assessed at 8-14, 26-28, and 34-36 weeks of gestation; weight retention was measured 2 mo postpartum.

RESULTS

The proportion of women meeting the guidelines was significantly greater in those receiving the intervention than UC (60.8% compared with 25.0%, OR: 4.7; 95% CI: 1.3, 16.2; P = 0.019). Furthermore, 36.4% of the intervention women were at or below their prepregnancy weight at 2 mo postpartum compared with 12.5% in the UC group (P = 0.05).

CONCLUSIONS

A multi-component behavioral intervention improved adherence to the 2009 Institute of Medicine weight-gain guidelines. This trial was registered with clinicaltrials.gov as NCT02168647.

Do lifestyle interventions during pregnancy have the potential to reduce long-term postpartum weight retention? A systematic review and meta-analysis

Reducing postpartum weight retention is a promising strategy for addressing the rising prevalence of overweight and obesity in women. This systematic review and meta-analysis explored whether lifestyle interventions during pregnancy have the potential to reduce weight retention at 4 months postpartum and beyond. A search of five electronic databases for randomized controlled trials comparing the effect of weight-related lifestyle interventions beginning in pregnancy on postpartum weight retention to standard prenatal care groups was performed. Postpartum weight retention data was synthesized in a random-effects meta-analysis. Data from 14 studies of 7116 participants showed that the intervention group retained statistically significant less weight than the control group (weighted mean difference: -0.73 kg, 95% CI: -1.32 to -0.14, P = 0.015). Subgroup analysis showed this effect to be largest in studies with follow-ups from 4 to 6 months (weighted mean difference: -1.32 kg, 95% CI: -2.11 to -0.53, P = 0.001), but it remained significant until 12 months postpartum (weighted mean difference: -0.68 kg, 95% CI: -1.28 to -0.09, P = 0.023). In studies of women with a body mass index above 25.0 kg/m² , no significant intervention effect was observed. More high-quality studies with a follow-up beyond 12 months postpartum are needed.

Does Partial Meal Replacement During Pregnancy Reduce 12-Month Postpartum Weight Retention?

OBJECTIVE

This randomized trial tested whether a behavioral intervention with meal replacements in pregnancy could increase the proportion of women who returned to prepregnancy weight and reduce postpartum weight retention by 12 months after delivery.

METHODS

Women (N = 264; 13.7 weeks' gestation) with overweight or obesity were randomly assigned to usual care or intervention. The intervention reduced excess gestational weight gain and was discontinued at delivery. At follow-up, 83.7% completed the 12-month assessment.

RESULTS

Compared with usual care, prenatal intervention had no significant effect on odds of achieving prepregnancy weight (38/128 [29.7%] vs. 41/129 [31.8%]; P = 0.98) or in reducing the magnitude of weight retained (3.3 vs. 3.1 kg; P = 0.82) at 12 months. After delivery, significant (P < 0.0001) declines in meal replacements, practice of weight control behaviors, and dietary restraint were observed in the intervention group. Independent of group, lower gestational weight gain was the strongest predictor of achieving prepregnancy weight at 12 months (P = 0.0008).

CONCLUSIONS

A prenatal behavioral intervention with meal replacements that reduced pregnancy weight gain had no significant effect on 12-month postpartum weight retention.

Nutrition and Exercise Strategies to Prevent Excessive Pregnancy Weight Gain: A Meta-analysis

Objective  To evaluate nutrition-only, exercise-only, and nutrition-plus-exercise interventions for optimizing gestational weight gain (GWG) based on the 2009 Institute of Medicine (IOM) guidelines. Study  PubMed, Google Scholar, and 2015 Cochrane Review were searched. Analysis of variance was used to determine if significant GWG differences exist between strategies, with additional subanalyses on overweight (OV) or obese women based on 2009 IOM guidelines. Results  Of 66 identified studies, 31 contributed data ( n  = 8,558). Compared with routine prenatal care, nutrition-only interventions were significantly associated with reduced GWG and are most likely to produce weight gain within IOM recommendations ( p  = 0.013). Exercise-only ( p  = 0.069) and nutrition-plus-exercise ( p  = 0.056) interventions trended toward GWG within IOM guidelines, but did not reach statistical significance. Supervised ( p  = 0.61) and unsupervised ( p  = 0.494) exercise programs had similar effectiveness. Subanalyses on OV or obese women produced similar results to studies that did not differentiate results based on body mass index: nutrition only ( p  = 0.011), exercise only ( p  = 0.308), and nutrition plus exercise ( p  = 0.129). Conclusion  Preventing excessive GWG is crucial, especially for OV or obese women. In the current study, nutrition-based intervention is the health system strategy that showed significant impact on preventing excessive GWG compared with routine prenatal care. Among women who are OV or have obesity, nutrition-only interventions hold the most promise compared with routine prenatal care.

High protein diet promotes body weight loss among Brazilian postpartum women

There is evidence in the general population that adhering to a high protein and low carbohydrate diet may help in losing weight. However, there is little evidence among postpartum women. The aim of this study is to evaluate the effect of a high protein diet on weight loss among postpartum women. A parallel-randomized controlled trial with 94 postpartum women was conducted in a maternity ward in Mesquita county (recruitment from February 2009 to December 2010) and in a polyclinic in Rio de Janeiro city (recruitment from December 2010 to December 2011). Women were randomized to the intervention group (IG) or control group (CG), and both groups received an isocaloric diet (1,800 kcal). Additionally, the IG received approximately 25 g of protein obtained from 125 g per week of sardine to increase daily dietary protein content and was advised to restrict carbohydrate intake. The CG received nutritional counselling to follow the national nutrition guidelines (15% protein, 60% carbohydrates, and 25% lipids). A linear mixed-effects model was used to test the effect of high protein intake and macronutrient intake on weight loss during the postpartum period. Body weight decreased in the IG compared with the CG (ß = -0.325; p = 0.049) among overweight and obese postpartum women. The percentage of energy intake from lipid (ß = -0.023; p = 0.050) was negatively associated with body weight, and carbohydrate intake (ß = 0.020; p = 0.026) was positively associated with body weight over time among all women. Protein intake and lower carbohydrate intake may be used as a dietary strategy to improve body weight loss during the postpartum period.

Attenuation of maternal weight gain impacts infant birthweight: systematic review and meta-analysis

Despite many interventions aiming to reduce excessive gestational weight gain (GWG), it is currently unclear the impact on infant anthropometric outcomes. The aim of this review was to evaluate offspring anthropometric outcomes in studies designed to reduce GWG. A systematic search of seven international databases, one clinical trial registry and three Chinese databases was conducted without date limits. Studies were categorised by intervention type: diet, physical activity (PA), lifestyle (diet + PA), other, gestational diabetes mellitus (GDM) (diet, PA, lifestyle, metformin and other). Meta-analyses were reported as weighted mean difference (WMD) for birthweight and birth length, and risk ratio (RR) for small for gestational age (SGA), large for gestational age (LGA), macrosomia and low birth weight (LBW). Collectively, interventions reduced birthweight, risk of macrosomia and LGA by 71 g (WMD: -70.67, 95% CI -101.90 to -39.43, P&lt;0.001), 16% (RR: 0.84, 95% CI 0.73-0.98, P=0.026) and 19% (RR: 0.81, 95% CI 0.69-0.96, P=0.015), respectively. Diet interventions decreased birthweight and LGA by 99 g (WMD -98.80, 95% CI -178.85 to -18.76, P=0.016) and 65% (RR: 0.35, 95% CI 0.17-0.72, P=0.004). PA interventions reduced the risk of macrosomia by 51% (RR: 0.49, 95% CI 0.26-0.92, P=0.036). In women with GDM, diet and lifestyle interventions reduced birthweight by 211 and 296 g, respectively (WMD: -210.93, 95% CI -374.77 to -46.71, P=0.012 and WMD:-295.93, 95% CI -501.76 to -90.10, P=0.005, respectively). Interventions designed to reduce excessive GWG lead to a small reduction in infant birthweight and risk of macrosomia and LGA, without influencing the risk of adverse outcomes including LBW and SGA.

Impact of prenatal exercise on maternal harms, labour and delivery outcomes: a systematic review and meta-analysis

OBJECTIVE

To perform a systematic review of the relationships between prenatal exercise and maternal harms including labour/delivery outcomes.

DESIGN

Systematic review with random effects meta-analysis and meta-regression.

DATASOURCES

Online databases were searched up to 6 January 2017.

STUDY ELIGIBILITY CRITERIA

Studies of all designs were included (except case studies) if they were published in English, Spanish or French and contained information on the population (pregnant women without contraindication to exercise), intervention (subjective or objective measures of frequency, intensity, duration, volume or type of exercise), comparator (no exercise or different frequency, intensity, duration, volume and type of exercise, alone ["exercise-only"] or in combination with other intervention components [e.g., dietary; "exercise + co-intervention"]) and outcome (preterm/prelabour rupture of membranes, caesarean section, instrumental delivery, induction of labour, length of labour, vaginal tears, fatigue, injury, musculoskeletal trauma, maternal harms (author defined) and diastasis recti).

RESULTS

113 studies (n=52 858 women) were included. 'Moderate' quality evidence from exercise-only randomised controlled trials (RCTs) indicated a 24% reduction in the odds of instrumental delivery in women who exercised compared with women who did not (20 RCTs, n=3819; OR 0.76, 95% CI 0.63 to 0.92, I ²= 0 %). The remaining outcomes were not associated with exercise. Results from meta-regression did not identify a dose-response relationship between frequency, intensity, duration or volume of exercise and labour and delivery outcomes.

SUMMARY/CONCLUSIONS

Prenatal exercise reduced the odds of instrumental delivery in the general obstetrical population. There was no relationship between prenatal exercise and preterm/prelabour rupture of membranes, caesarean section, induction of labour, length of labour, vaginal tears, fatigue, injury, musculoskeletal trauma, maternal harms and diastasis recti.

Impact of prenatal exercise on neonatal and childhood outcomes: a systematic review and meta-analysis

Objective

We aimed to identify the relationship between maternal prenatal exercise and birth complications, and neonatal and childhood morphometric, metabolic and developmental outcomes.

Design

Systematic review with random-effects meta-analysis and meta-regression.

Data sources

Online databases were searched up to 6 January 2017.

Study eligibility criteria

Studies of all designs were eligible (except case studies and reviews) if published in English, Spanish or French, and contained information on the relevant population (pregnant women without contraindication to exercise), intervention (subjective/objective measures of frequency, intensity, duration, volume or type of exercise, alone (‘exercise-only’) or in combination with other intervention components (eg, dietary; ‘exercise+cointervention’)), comparator (no exercise or different frequency, intensity, duration, volume, type or trimester of exercise) and outcomes (preterm birth, gestational age at delivery, birth weight, low birth weight (<2500 g), high birth weight (>4000 g), small for gestational age, large for gestational age, intrauterine growth restriction, neonatal hypoglycaemia, metabolic acidosis (cord blood pH, base excess), hyperbilirubinaemia, Apgar scores, neonatal intensive care unit admittance, shoulder dystocia, brachial plexus injury, neonatal body composition (per cent body fat, body weight, body mass index (BMI), ponderal index), childhood obesity (per cent body fat, body weight, BMI) and developmental milestones (including cognitive, psychosocial, motor skills)).

Results

A total of 135 studies (n=166 094) were included. There was ‘high’ quality evidence from exercise-only randomised controlled trials (RCTs) showing a 39% reduction in the odds of having a baby >4000 g (macrosomia: 15 RCTs, n=3670; OR 0.61, 95% CI 0.41 to 0.92) in women who exercised compared with women who did not exercise, without affecting the odds of growth-restricted, preterm or low birth weight babies. Prenatal exercise was not associated with the other neonatal or infant outcomes that were examined.

Conclusions

Prenatal exercise is safe and beneficial for the fetus. Maternal exercise was associated with reduced odds of macrosomia (abnormally large babies) and was not associated with neonatal complications or adverse childhood outcomes.

Effectiveness of exercise interventions in the prevention of excessive gestational weight gain and postpartum weight retention: a systematic review and meta-analysis

Objective

Gestational weight gain (GWG) has been identified as a critical modifier of maternal and fetal health. This systematic review and meta-analysis aimed to examine the relationship between prenatal exercise, GWG and postpartum weight retention (PPWR).

Design

Systematic review with random effects meta-analysis and meta-regression. Online databases were searched up to 6 January 2017.

Study eligibility criteria

Studies of all designs in English, Spanish or French were eligible (except case studies and reviews) if they contained information on the population (pregnant women without contraindication to exercise), intervention (frequency, intensity, duration, volume or type of exercise, alone [“exercise-only”] or in combination with other intervention components [eg, dietary; “exercise + co-intervention”]), comparator (no exercise or different frequency, intensity, duration, volume or type of exercise) and outcomes (GWG, excessive GWG (EGWG), inadequate GWG (IGWG) or PPWR).

Results

Eighty-four unique studies (n=21 530) were included. ‘Low’ to ‘moderate’ quality evidence from randomised controlled trials (RCTs) showed that exercise-only interventions decreased total GWG (n=5819; −0.9 kg, 95% CI −1.23 to –0.57 kg, I2=52%) and PPWR (n=420; −0.92 kg, 95% CI −1.84 to 0.00 kg, I2=0%) and reduced the odds of EGWG (n=3519; OR 0.68, 95% CI 0.57 to 0.80, I2=12%) compared with no exercise. ‘High’ quality evidence indicated higher odds of IGWG with prenatal exercise-only (n=1628; OR 1.32, 95% CI 1.04 to 1.67, I2=0%) compared with no exercise.

Conclusions

Prenatal exercise reduced the odds of EGWG and PPWR but increased the risk of IGWG. However, the latter result should be interpreted with caution because it was based on a limited number of studies (five RCTs).

Attenuating Pregnancy Weight Gain-What Works and Why: A Systematic Review and Meta-Analysis

Excessive maternal gestational weight gain (GWG) contributes to generational obesity. Our aim was to explore efficacy and intervention characteristics (trimester, duration, frequency, intensity, and delivery method) of interventions to prevent excessive GWG. CINAHL, Cochrane, EMBASE, LILACS, MEDLINE, PsycINFO, and Scopus were searched up to May 2018 (no date or language restrictions). Keywords and MeSH terms for diet, GWG, intervention, lifestyle, maternal, physical activity, and pregnancy were used to locate randomized-controlled trials (RCTs). The Cochrane Collaboration tool for assessing risk of bias was applied. Eighty-nine RCTs were included. Meta-analysis (60 trials) estimated that women in diet only (WMD: -3.27; 95% CI: -4.96, -1.58, p < 0.01), physical activity (PA) (WMD: -1.02; 95% CI: -1.56, -0.49, p < 0.01), and lifestyle interventions (combining diet and PA) (WMD: -0.84; 95% CI: -1.29, -0.39, p < 0.01) gained significantly less weight than controls. The three eHealth interventions favored neither intervention nor control (WMD: -1.06; 95% CI: -4.13, 2.00, p = 0.50). Meta-regression demonstrated no optimal duration, frequency, intensity, setting, or diet type. Traditional face to face delivery of weight management interventions during pregnancy can be successful. Delivery via eHealth has potential to extend its reach to younger women but needs further evaluation of its success.

Eating Behaviors in Postpartum: A Qualitative Study of Women with Obesity

In postpartum, women experience major changes in their lives; they are forced to deal with new internal and external demands for attention and care for themselves and the baby. Postpartum feeding also suffers changes in this stage of life, because women find more barriers to healthy eating, which can put them at greater risk of overweight or obesity. This is a qualitative study, through in-depth semi-directed interviews in an intentional sample with postpartum women with obesity, closed by saturation and qualitative content analysis. Sixteen women were included. Three categories emerged from this analysis: (1) from pregnancy to postpartum: changes in body and eating behavior; (2) eating to fill the void of helplessness felt during the postpartum period; and (3) breastfeeding and baby feeding. Women with obesity eat to relieve unpleasant feelings during the postnatal period. The postpartum period is an opportune moment to introduce long-term changes in the eating behaviors and mental wellbeing of these women. Healthcare teams need to restructure to provide more focused follow-up care for women with obesity during the postnatal period in terms of their physical and emotional health.

Effects of antenatal diet and physical activity on maternal and fetal outcomes: individual patient data meta-analysis and health economic evaluation

BACKGROUND

Diet- and physical activity-based interventions in pregnancy have the potential to alter maternal and child outcomes.

OBJECTIVES

To assess whether or not the effects of diet and lifestyle interventions vary in subgroups of women, based on maternal body mass index (BMI), age, parity, Caucasian ethnicity and underlying medical condition(s), by undertaking an individual patient data (IPD) meta-analysis. We also evaluated the association of gestational weight gain (GWG) with adverse pregnancy outcomes and assessed the cost-effectiveness of the interventions.

DATA SOURCES

MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects and Health Technology Assessment database were searched from October 2013 to March 2015 (to update a previous search).

REVIEW METHODS

Researchers from the International Weight Management in Pregnancy Collaborative Network shared the primary data. For each intervention type and outcome, we performed a two-step IPD random-effects meta-analysis, for all women (except underweight) combined and for each subgroup of interest, to obtain summary estimates of effects and 95% confidence intervals (CIs), and synthesised the differences in effects between subgroups. In the first stage, we fitted a linear regression adjusted for baseline (for continuous outcomes) or a logistic regression model (for binary outcomes) in each study separately; estimates were combined across studies using random-effects meta-analysis models. We quantified the relationship between weight gain and complications, and undertook a decision-analytic model-based economic evaluation to assess the cost-effectiveness of the interventions.

RESULTS

Diet and lifestyle interventions reduced GWG by an average of 0.70 kg (95% CI -0.92 to -0.48 kg; 33 studies, 9320 women). The effects on composite maternal outcome [summary odds ratio (OR) 0.90, 95% CI 0.79 to 1.03; 24 studies, 8852 women] and composite fetal/neonatal outcome (summary OR 0.94, 95% CI 0.83 to 1.08; 18 studies, 7981 women) were not significant. The effect did not vary with baseline BMI, age, ethnicity, parity or underlying medical conditions for GWG, and composite maternal and fetal outcomes. Lifestyle interventions reduce Caesarean sections (OR 0.91, 95% CI 0.83 to 0.99), but not other individual maternal outcomes such as gestational diabetes mellitus (OR 0.89, 95% CI 0.72 to 1.10), pre-eclampsia or pregnancy-induced hypertension (OR 0.95, 95% CI 0.78 to 1.16) and preterm birth (OR 0.94, 95% CI 0.78 to 1.13). There was no significant effect on fetal outcomes. The interventions were not cost-effective. GWG, including adherence to the Institute of Medicine-recommended targets, was not associated with a reduction in complications. Predictors of GWG were maternal age (summary estimate -0.10 kg, 95% CI -0.14 to -0.06 kg) and multiparity (summary estimate -0.73 kg, 95% CI -1.24 to -0.23 kg).

LIMITATIONS

The findings were limited by the lack of standardisation in the components of intervention, residual heterogeneity in effects across studies for most analyses and the unavailability of IPD in some studies.

CONCLUSION

Diet and lifestyle interventions in pregnancy are clinically effective in reducing GWG irrespective of risk factors, with no effects on composite maternal and fetal outcomes.

FUTURE WORK

The differential effects of lifestyle interventions on individual pregnancy outcomes need evaluation.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013003804.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Antepartum Care of Women Who Are Obese During Pregnancy: Systematic Review of the Current Evidence

INTRODUCTION

Nearly 40% of US women of childbearing age are obese. Obesity during pregnancy is associated with multiple risks for both the woman and fetus, yet clinicians often feel unprepared to provide optimal antepartum care for this group of women. We collected and reviewed current evidence concerning antepartum care of women who are obese during pregnancy.

METHODS

We conducted a systematic review using PRISMA guidelines. Current evidence relating to the pregnancy care of women with a prepregnancy body mass index of 30kg/m2 or higher was identified using MEDLINE databases via PubMed, Embase, and Web of Science Core Collection between January 2012 and February 2018.

RESULTS

A total of 354 records were located after database searches, of which 63 met inclusion criteria. Topic areas for of included studies were: pregnancy risk and outcomes related to obesity, communication between women and health care providers, gestational weight gain and activity/diet, diabetic disorders, hypertensive disorders, obstructive sleep apnea, mental health, pregnancy imaging and measurement, late antepartum care, and preparation for labor and birth.

DISCUSSION

Midwives and other health care providers can provide better antepartum care to women who are obese during pregnancy by incorporating evidence from the most current clinical investigations.

Effect of dietary counseling on preventing excessive weight gain during pregnancy

OBJECTIVES

Excessive gestational weight gain (EGWG) is associated with short- and long-term health problems among mothers and their offspring. The aim of this study was to assess the effect of dietary counseling on EGWG.

STUDY DESIGN

Randomized controlled intervention trial.

METHODS

The study was conducted at the antenatal care (ANC) clinic, Center for Social and Preventive Medicine, Pediatrics Hospital, Cairo University, during the period from July 2015 to April 2016. A total of 200 primigravidae aged between 20 and 30 years were included and randomized into intervention and control groups. Based on data analysis from phase 1, nutritional practices of the studied participants were identified and tailored nutrition counseling sessions designed. Follow-up of the studied participants throughout ANC visits was done to enforce the healthy dietary intake and encourage weight gain according to the recommendations to avoid EGWG.

RESULTS

The intervention resulted in a significantly higher proportion of women in the intervention group who gained gestational weight within the Institute of Medicine recommendations compared to women in the control group (42.7% vs 13.9%, respectively) (P-value <0.001); this was detected between the 25th and 35th weeks of gestation. Dietary counseling had significantly improved the frequency of consumption of different food items and knowledge, attitude, and practice mean scores of the intervention group in comparison with the control group (P-value <0.001).

CONCLUSIONS

The results of the present study demonstrated that dietary counseling given to pregnant women reduced the proportion of EGWG and improved dietary practices. There is a strong need for effective intervention strategies targeting EGWG to prevent adverse pregnancy outcomes.

Maternal weight in the postpartum: results from the Delta healthy sprouts trial

Background

Excessive postnatal weight retention may pose a threat to a woman’s health and future pregnancies. Women in the Lower Mississippi Delta (LMD) region of Mississippi suffer from among the highest rates of obesity in the U.S. and are more likely to gain an excessive amount of weight during pregnancy. The aim of this study was to determine if LMD women who received a lifestyle enhanced maternal, infant, and early childhood home visiting (MIECHV) curriculum had more favorable weight outcomes through 12-months postpartum compared to women who received a standard MIECHV curriculum.

Methods

Delta Healthy Sprouts was a two-arm, randomized, controlled, comparative impact trial. Pregnant women at least 18 years of age, less than 19 weeks pregnant with a singleton pregnancy, and residing in the LMD region were recruited. On a monthly basis in the participant’s home, the control arm (PAT) received the Parents as Teachers curriculum while the experimental arm (PATE) received a lifestyle enhanced Parents as Teachers curriculum. Pre-pregnancy body weight via self-report and maternal body weight at baseline (gestational month 4) and at every subsequent monthly visit through 12 months postpartum was measured. Linear mixed models were used to test for significant treatment, time, and treatment by time effects on postnatal weight outcomes.

Results

Mean postnatal weight losses were 0.8 and 1.1 kg at postnatal month (PM) 6 and PM 12, respectively, for PAT participants. Mean postnatal weight losses for PATE participants were 1.5 and 1.2 kg at PM 6 and PM 12, respectively. Mean weight retention, based on pre-pregnancy weight, were 5.2, 4.0, and 3.6 kg at PM 1, PM 6, and PM 12, respectively, for PAT participants. Mean weight retention for PATE participants were 6.3, 4.5, and 4.0 kg at PM 1, PM 6, and PM 12, respectively. Significant effects were not found for treatment, time, or treatment by time.

Conclusions

An enhanced MIECHV curriculum was not associated with more favorable postpartum weight outcomes when compared to a standard MIECHV curriculum in a cohort of LMD women during the 12 months following the birth of their infant. Trial registration: clinicaltrials.gov, NCT01746394. Registered 5 December 2012.

Combined diet and exercise interventions for preventing gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with a wide range of adverse health consequences for women and their infants in the short and long term. With an increasing prevalence of GDM worldwide, there is an urgent need to assess strategies for GDM prevention, such as combined diet and exercise interventions. This is an update of a Cochrane review that was first published in 2015.

OBJECTIVES

To assess the effects of diet interventions in combination with exercise interventions for pregnant women for preventing GDM, and associated adverse health consequences for the mother and her infant/child.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (27 November 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and cluster-RCTs, comparing combined diet and exercise interventions with no intervention (i.e. standard care), that reported on GDM diagnosis as an outcome. Quasi-RCTs were excluded. Cross-over trials were not eligible for inclusion. We planned to include RCTs comparing two or more different diet/exercise interventions, however none were identified.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data, assessed the risk of bias of the included trials and assessed quality of evidence for selected maternal and infant/child outcomes using the GRADE approach. We checked data for accuracy.

MAIN RESULTS

In this update, we included 23 RCTs (involving 8918 women and 8709 infants) that compared combined diet and exercise interventions with no intervention (standard care). The studies varied in the diet and exercise programs evaluated and health outcomes reported. None reported receiving funding from a drug manufacturer or agency with interests in the results. Overall risk of bias was judged to be unclear due to the lack of methodological detail reported. Most studies were undertaken in high-income countries.For our primary review outcomes, there was a possible reduced risk of GDM in the diet and exercise intervention group compared with the standard care group (average risk ratio (RR) 0.85, 95% confidence interval (CI) 0.71 to 1.01; 6633 women; 19 RCTs; Tau² = 0.05; I² = 42%; P = 0.07; moderate-quality evidence). There was also a possible reduced risk of caesarean section (RR 0.95, 95% CI 0.88 to 1.02; 6089 women; 14 RCTs; moderate-quality evidence). No clear differences were seen between groups for pre-eclampsia (RR 0.98, 95% CI 0.79 to 1.22; 5366 participants; 8 RCTs; low-quality evidence), pregnancy-induced hypertension and/or hypertension (average RR 0.78, 95% CI 0.47 to 1.27; 3073 participants; 6 RCTs; Tau² = 0.19; I² = 62%; very low-quality evidence), perinatal mortality (RR 0.82, 95% CI 0.42 to 1.63; 3757 participants; 2 RCTs; low-quality evidence) or large-for-gestational age (RR 0.93, 95% CI 0.81 to 1.07; 5353 participants; 11 RCTs; low-quality evidence). No data were reported for infant mortality or morbidity composite.Subgroup analyses (based on trial design, maternal body mass index (BMI) and ethnicity) revealed no clear differential treatment effects. We were unable to assess the impact of maternal age, parity and specific features of the diet and exercise interventions. Findings from sensitivity analyses (based on RCT quality) generally supported those observed in the main analyses. We were not able to perform subgroup analyses based on maternal age, parity or nature of the exercise/dietary interventions due to the paucity of information/data on these characteristics and the inability to meaningfully group intervention characteristics.For most of the secondary review outcomes assessed using GRADE, there were no clear differences between groups, including for perineal trauma (RR 1.27, 95% CI 0.78 to 2.05; 2733 participants; 2 RCTs; moderate-quality evidence), neonatal hypoglycaemia (average RR 1.42, 95% CI 0.67 to 2.98; 3653 participants; 2 RCTs; Tau² = 0.23; I² = 77%; low quality evidence); and childhood adiposity (BMI z score) (MD 0.05, 95% CI -0.29 to 0.40; 794 participants; 2 RCTs; Tau² = 0.04; I² = 59%; low-quality evidence). However, there was evidence of less gestational weight gain in the diet and exercise intervention group compared with the control group (mean difference (MD) -0.89 kg, 95% CI -1.39 to -0.40; 5052 women; 16 RCTs; Tau² = 0.37; I² = 43%;moderate-quality evidence). No data were reported for maternal postnatal depression or type 2 diabetes; childhood/adulthood type 2 diabetes, or neurosensory disability.

AUTHORS' CONCLUSIONS

Moderate-quality evidence suggests reduced risks of GDM and caesarean section with combined diet and exercise interventions during pregnancy as well as reductions in gestational weight gain, compared with standard care. There were no clear differences in hypertensive disorders of pregnancy, perinatal mortality, large-for-gestational age, perineal trauma, neonatal hypoglycaemia, and childhood adiposity (moderate- tovery low-quality evidence).Using GRADE methodology, the evidence was assessed as moderate to very low quality. Downgrading decisions were predominantly due to design limitations (risk of bias), and imprecision (uncertain effect estimates, and at times, small sample sizes and low event rates), however two outcomes (pregnancy-induced hypertension/hypertension and neonatal hypoglycaemia), were also downgraded for unexplained inconsistency (statistical heterogeneity).Due to the variability of the diet and exercise components tested in the included studies, the evidence in this review has limited ability to inform practice. Future studies could describe the interventions used in more detail, if and how these influenced behaviour change and ideally be standardised between studies. Studies could also consider using existing core outcome sets to facilitate more standardised reporting.

Exercise during pregnancy and its impact on mothers and offspring in humans and mice

Exercise during pregnancy has beneficial effects on maternal and offspring’s health in humans and mice. The underlying mechanisms remain unclear. This comparative study aimed to determine the long-term effects of an exercise program on metabolism, weight gain, body composition and changes in hormones [insulin, leptin, brain-derived neurotrophic factor (BDNF)]. Pregnant women (n=34) and mouse dams (n=44) were subjected to an exercise program compared with matched controls (period I). Follow-up in the offspring was performed over 6 months in humans, corresponding to postnatal day (P) 21 in mice (period II). Half of the mouse offspring was challenged with a high-fat diet (HFD) for 6 weeks between P70 and P112 (period III). In period I, exercise during pregnancy led to 6% lower fat content, 40% lower leptin levels and an increase of 50% BDNF levels in humans compared with controls, which was not observed in mice. After period II in humans and mice, offspring body weight did not differ from that of the controls. Further differences were observed in period III. Offspring of exercising mouse dams had significantly lower fat mass and leptin levels compared with controls. In addition, at P112, BDNF levels in offspring were significantly higher from exercising mothers while this effect was completely blunted by HFD feeding. In this study, we found comparable effects on maternal and offspring’s weight gain in humans and mice but different effects in insulin, leptin and BDNF. The long-term potential protective effects of exercise on biomarkers should be examined in human studies.

Effect of diet and physical activity based interventions in pregnancy on gestational weight gain and pregnancy outcomes: meta-analysis of individual participant data from randomised trials

Objective To synthesise the evidence on the overall and differential effects of interventions based on diet and physical activity during pregnancy, primarily on gestational weight gain and maternal and offspring composite outcomes, according to women's body mass index, age, parity, ethnicity, and pre-existing medical condition; and secondarily on individual complications.Design Systematic review and meta-analysis of individual participant data (IPD). Data sources Major electronic databases from inception to February 2017 without language restrictions.Eligibility criteria for selecting studies Randomised trials on diet and physical activity based interventions in pregnancy.Data synthesis Statistical models accounted for clustering of participants within trials and heterogeneity across trials leading to summary mean differences or odds ratios with 95% confidence intervals for the effects overall, and in subgroups (interactions).Results IPD were obtained from 36 randomised trials (12 526 women). Less weight gain occurred in the intervention group than control group (mean difference -0.70 kg, 95% confidence interval -0.92 to -0.48 kg, I²=14.1%; 33 studies, 9320 women). Although summary effect estimates favoured the intervention, the reductions in maternal (odds ratio 0.90, 95% confidence interval 0.79 to 1.03, I²=26.7%; 24 studies, 8852 women) and offspring (0.94, 0.83 to 1.08, I²=0%; 18 studies, 7981 women) composite outcomes were not statistically significant. No evidence was found of differential intervention effects across subgroups, for either gestational weight gain or composite outcomes. There was strong evidence that interventions reduced the odds of caesarean section (0.91, 0.83 to 0.99, I²=0%; 32 studies, 11 410 women), but not for other individual complications in IPD meta-analysis. When IPD were supplemented with study level data from studies that did not provide IPD, the overall effect was similar, with stronger evidence of benefit for gestational diabetes (0.76, 0.65 to 0.89, I²=36.8%; 59 studies, 16 885 women).Conclusion Diet and physical activity based interventions during pregnancy reduce gestational weight gain and lower the odds of caesarean section. There is no evidence that effects differ across subgroups of women.

What characteristics of nutrition and physical activity interventions are key to effectively reducing weight gain in obese or overweight pregnant women? A systematic review and meta-analysis

Lifestyle interventions targeting gestational weight gain (GWG) report varying degrees of success. To better understand factors influencing efficacy, we reviewed randomized trials specifically among obese and overweight pregnant women.

METHODS

We conducted a systematic review and a meta-analysis of 32 studies with a pooled population of 5,869 overweight or obese pregnant women. Random effects models were fit to compute the weighted mean difference (WMD) in GWG between groups across studies. Subgroup analyses were conducted to compare intervention efficacy in overweight vs. obese pregnant women, and interventions delivered by prenatal care providers (PCPs) vs. non-PCPs during pregnancy. Moderator analyses ensured.

RESULTS

Nine (28%) of 32 studies reported significant reductions in GWG in response to intervention. Of these, six (66%) of nine were delivered by PCPs. Overall, the WMD in GWG was -1.71 (95% confidence interval [CI]: -2.55, -0.86) kg. However, interventions delivered by PCPs yielded a significantly greater reduction in GWG compared to interventions delivered by non-PCPs (WMD = -3.88 kg; 95% CI: -7.01, -0.75 vs. -0.80 kg; 95% CI: -1.32, -0.28; p for difference = 0.005).

CONCLUSION

When PCPs counsel nutrition and physical activity, obese and overweight pregnant women have greater success meeting GWG targets and may be more motivated to modify their behaviour than with other modes of intervention deliveries.

Dietary advice interventions in pregnancy for preventing gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) is a form of diabetes occurring during pregnancy which can result in short- and long-term adverse outcomes for women and babies. With an increasing prevalence worldwide, there is a need to assess strategies, including dietary advice interventions, that might prevent GDM.

OBJECTIVES

To assess the effects of dietary advice interventions for preventing GDM and associated adverse health outcomes for women and their babies.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register (3 January 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs assessing the effects of dietary advice interventions compared with no intervention (standard care), or to different dietary advice interventions. Cluster-RCTs were eligible for inclusion but none were identified.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data and assessed the risk of bias of the included studies. Data were checked for accuracy. The quality of the evidence was assessed using the GRADE approach.

MAIN RESULTS

We included 11 trials involving 2786 women and their babies, with an overall unclear to moderate risk of bias. Six trials compared dietary advice interventions with standard care; four compared low glycaemic index (GI) with moderate- to high-GI dietary advice; one compared specific (high-fibre focused) with standard dietary advice. Dietary advice interventions versus standard care (six trials) Considering primary outcomes, a trend towards a reduction in GDM was observed for women receiving dietary advice compared with standard care (average risk ratio (RR) 0.60, 95% confidence interval (CI) 0.35 to 1.04; five trials, 1279 women; Tau² = 0.20; I² = 56%; P = 0.07; GRADE: very low-quality evidence); subgroup analysis suggested a greater treatment effect for overweight and obese women receiving dietary advice. While no clear difference was observed for pre-eclampsia (RR 0.61, 95% CI 0.25 to 1.46; two trials, 282 women; GRADE: low-quality evidence) a reduction in pregnancy-induced hypertension was observed for women receiving dietary advice (RR 0.30, 95% CI 0.10 to 0.88; two trials, 282 women; GRADE: low-quality evidence). One trial reported on perinatal mortality, and no deaths were observed (GRADE: very low-quality evidence). None of the trials reported on large-for-gestational age or neonatal mortality and morbidity.For secondary outcomes, no clear differences were seen for caesarean section (average RR 0.98, 95% CI 0.78 to 1.24; four trials, 1194 women; Tau² = 0.02; I² = 36%; GRADE: low-quality evidence) or perineal trauma (RR 0.83, 95% CI 0.23 to 3.08; one trial, 759 women; GRADE: very low-quality evidence). Women who received dietary advice gained less weight during pregnancy (mean difference (MD) -4.70 kg, 95% CI -8.07 to -1.34; five trials, 1336 women; Tau² = 13.64; I² = 96%; GRADE: low-quality evidence); the result should be interpreted with some caution due to considerable heterogeneity. No clear differences were seen for the majority of secondary outcomes reported, including childhood/adulthood adiposity (skin-fold thickness at six months) (MD -0.10 mm, 95% CI -0.71 to 0.51; one trial, 132 children; GRADE: low-quality evidence). Women receiving dietary advice had a lower well-being score between 14 and 28 weeks, more weight loss at three months, and were less likely to have glucose intolerance (one trial).The trials did not report on other secondary outcomes, particularly those related to long-term health and health service use and costs. We were not able to assess the following outcomes using GRADE: postnatal depression; maternal type 2 diabetes; neonatal hypoglycaemia; childhood/adulthood type 2 diabetes; and neurosensory disability. Low-GI dietary advice versus moderate- to high-GI dietary advice (four trials) Considering primary outcomes, no clear differences were shown in the risks of GDM (RR 0.91, 95% CI 0.63 to 1.31; four trials, 912 women; GRADE: low-quality evidence) or large-for-gestational age (average RR 0.60, 95% CI 0.19 to 1.86; three trials, 777 babies; Tau² = 0.61; P = 0.07; I² = 62%; GRADE: very low-quality evidence) between the low-GI and moderate- to high-GI dietary advice groups. The trials did not report on: hypertensive disorders of pregnancy; perinatal mortality; neonatal mortality and morbidity.No clear differences were shown for caesarean birth (RR 1.27, 95% CI 0.79 to 2.04; two trials, 201 women; GRADE: very low-quality evidence) and gestational weight gain (MD -1.23 kg, 95% CI -4.08 to 1.61; four trials, 787 women; Tau² = 7.31; I² = 90%; GRADE: very low-quality evidence), or for other reported secondary outcomes.The trials did not report the majority of secondary outcomes including those related to long-term health and health service use and costs. We were not able to assess the following outcomes using GRADE: perineal trauma; postnatal depression; maternal type 2 diabetes; neonatal hypoglycaemia; childhood/adulthood adiposity; type 2 diabetes; and neurosensory disability. High-fibre dietary advice versus standard dietary advice (one trial) The one trial in this comparison reported on two secondary outcomes. No clear difference between the high-fibre and standard dietary advice groups observed for mean blood glucose (following an oral glucose tolerance test at 35 weeks), and birthweight.

AUTHORS' CONCLUSIONS

Very low-quality evidence from five trials suggests a possible reduction in GDM risk for women receiving dietary advice versus standard care, and low-quality evidence from four trials suggests no clear difference for women receiving low- versus moderate- to high-GI dietary advice. A possible reduction in pregnancy-induced hypertension for women receiving dietary advice was observed and no clear differences were seen for other reported primary outcomes. There were few outcome data for secondary outcomes.For outcomes assessed using GRADE, evidence was considered to be low to very low quality, with downgrading based on study limitations (risk of bias), imprecision, and inconsistency.More high-quality evidence is needed to determine the effects of dietary advice interventions in pregnancy. Future trials should be designed to monitor adherence, women's views and preferences, and powered to evaluate effects on short- and long-term outcomes; there is a need for such trials to collect and report on core outcomes for GDM research. We have identified five ongoing studies and four are awaiting classification. We will consider these in the next review update.

Dietary interventions in overweight and obese pregnant women: a systematic review of the content, delivery, and outcomes of randomized controlled trials

CONTEXT

Interventions targeting maternal obesity are a healthcare and public health priority.

OBJECTIVE

The objective of this review was to evaluate the adequacy and effectiveness of the methodological designs implemented in dietary intervention trials for obesity in pregnancy.

DATA SOURCES

A systematic review of the literature, consistent with PRISMA guidelines, was performed as part of the International Weight Management in Pregnancy collaboration.

STUDY SELECTION

Thirteen randomized controlled trials, which aimed to modify diet and physical activity in overweight and obese pregnant women, were identified.

DATA SYNTHESIS

There was significant variability in the content, delivery, and dietary assessment methods of the dietary interventions examined. A number of studies demonstrated improved dietary behavior in response to diet and/or lifestyle interventions. Nine studies reduced gestational weight gain.

CONCLUSION

This review reveals large methodological variability in dietary interventions to control gestational weight gain and improve clinical outcomes in overweight and obese pregnant women. This lack of consensus limits the ability to develop clinical guidelines and apply the evidence in clinical practice.

One-year postpartum outcomes following a weight management intervention in pregnant women with obesity

OBJECTIVE

This analysis was focused on 1-year maternal and infant follow-up of a randomized trial that tested a weight management intervention conducted during pregnancy.

METHODS

One hundred fourteen women with obesity (mean BMI 36.7 kg/m(2) ) were randomly assigned at a mean of 15 weeks gestation to a weight management intervention or usual care control condition. The intervention ended at delivery and resulted in less gestational weight gain and a lower proportion of large-for-gestational-age newborns among intervention compared with control participants. The primary outcome at 12 months postpartum was maternal weight. Secondary outcomes included infant weight-for-age and weight-for-length z-scores.

RESULTS

At 1 year, mothers in the intervention group weighed 96.3 ± 18.6 kg and those in the control group 99.7 ± 19.2 kg. There was no significant difference between groups in change in weight from randomization to 1 year postpartum (b = -0.47, 95% CI: -4.03 to 3.08). There was a significant main effect of group for infant weight-for-age z-scores (b = -0.40, 95% CI: -0.75 to -0.05) but not infant weight-for-length z-scores (b = -0.20, 95% CI: -0.59 to 0.20).

CONCLUSIONS

A gestational weight management intervention did not influence maternal weight or infant weight-for-length at 1 year postpartum. Future studies may be warranted to determine whether extending prenatal interventions into the postpartum period would be beneficial for maternal and infant outcomes.