Rate of gestational weight gain and preterm birth in relation to prepregnancy body mass indices and trimester: a follow-up study in China

Association between area under the curve of oral glucose tolerance test and the risk of preterm birth among women with gestational diabetes mellitus: a mediation effect of gestational weight gain

BACKGROUND

The risk of preterm birth (PTB) is associated with maternal hyperglycemia but differs by combinations of abnormal oral glucose tolerance test (OGTT) values. However, the potential pathway by which maternal hyperglycemia affects PTB is unclear. This study aimed to investigate the association between OGTT-related measures and PTB and evaluate the mediation effect of gestational weight gain (GWG) on the association between maternal hyperglycemia and the risk of PTB in women with gestational diabetes mellitus (GDM).

METHODS

This retrospective cohort study included women with GDM from a women's and children's hospital in Chengdu, China, from December 2021 to December 2023. The associations between OGTT-related measures, GWG, and PTB were evaluated by logistic regression analyses. Two-step clustering was used to classify participants by area under the curve (AUC) of the OGTT. SPSS Process Macro was utilized to explore the mediation effect of GWG on the relationship between AUC and PTB.

RESULTS

This study included 1860 women with GDM, of whom 694 (37.3%) women had higher AUC (≥ 17 mmol/L·h), 935 (50.3%) women had insufficient GWG, and 132 (7.1%) women had PTB. Multivariable logistic regression analyses showed that only higher AUC was associated with increased odds of PTB (OR:1.47, 95% CI:1.03 to 2.10; P = 0.036), and no significant associations between other OGTT-related measures and PTB were observed. Besides, GDM women with higher AUC had a higher risk of insufficient GWG (OR:1.23, 95% CI:1.02 to 1.49; P = 0.033), which was associated with increased odds of PTB (OR:2.15, 95% CI:1.47 to 3.14; P < 0.001). Mediation analyses revealed that the effect of AUC on PTB was mainly mediated through GWG (indirect effect: 0.15, bootstrapped 95% CI: 0.08 to 0.24).

CONCLUSIONS

This study found that AUC of the OGTT was positively associated with the occurrence of PTB, and GWG mainly mediated this positive association. Effective intervention strategies for GDM should pay close attention to avoiding insufficient GWG when managing their blood glucose, especially for those with higher AUC levels, to reduce the impact of maternal hyperglycemia on the risk of PTB.

Association of obesity with ropivacaine and sufentanil EC50 in labor analgesia: a single-center prospective study

OBJECTIVE

In part I, measure the EC50 of sufentanil in obese and non-obese parturients combined with 0.1% ropivacaine and compare the differences. Similarly, in part II, measure the EC50 of ropivacaine in obese and non-obese parturients combined with 0.5 µg/ml sufentanil and compare the differences.

METHODS

This study comprises two parts, with an initial intention to enroll 120 full-term primiparous women who underwent vaginal delivery and sought epidural analgesia. Each part includes an obese group (OA group, Obese Adults, defined as prepartum BMI≥29 kg/m2) and a non-obese group (CON group, Control group, defined as 18.5

RESULTS

In part I, the EC50 of epidural sufentanil in the OA group was 0.090 µg/ml (95% CI, 0.061~0.115µg/ml), and in the CON group, it was 0.170µg/ml (95% CI, 0.117~0.219µg/ml). In part II, the EC50 of epidural ropivacaine in the OA group was 0.048% (95% CI, 0.041~0.053%), and in the CON group, it was 0.070% (95% CI, 0.064~0.075%). The secondary outcomes in both parts of the study showed no statistically significant differences.

CONCLUSION

Obese parturients exhibited significantly lower EC50 values for ropivacaine and sufentanil compared to non-obese parturients. Lower concentrations of both agents can be considered for labor analgesia in obese parturients.

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Key Words

• Obese parturients; Epidural labor analgesia; EC50; Dose–response relationship

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MESH Headings

• Humans
• Female
• Sufentanil/administration & dosage
• Sufentanil/pharmacology
• Ropivacaine/administration & dosage
• Ropivacaine/pharmacology
• Pregnancy
• Adult
• Obesity/complications
• Anesthetics, Local/administration & dosage
• Analgesia, Obstetrical/methods
• Prospective Studies
• Analgesics, Opioid/administration & dosage
• Analgesia, Epidural/methods
• Young Adult
• Labor, Obstetric

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Grants

• SKY2021042 the Suzhou Science and Technology Development Plan Project Fund

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Affiliation(s)

Zunyi Liu Department of Anesthesiology, the Second Afffliated Hospital of Soochow University, Suzhou City, People's Republic of China Department of Anesthesiology, the First Afffliated Hospital of Ningbo University, Ningbo City, People's Republic of China
Xuelan Zhou Department of Anesthesiology, the Second Afffliated Hospital of Soochow University, Suzhou City, People's Republic of China
Jiang Zhu Department of Anesthesiology, the Second Afffliated Hospital of Soochow University, Suzhou City, People's Republic of China.

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The association of maternal gestational weight gain with cardiometabolic risk factors in offspring: a systematic review and meta-analysis

CONTEXT

Gestational weight gain (GWG) is known to be a risk factor for offspring obesity, a precursor of cardiometabolic diseases. Accumulating studies have investigated the association of GWG with offspring cardiometabolic risk factors (CRFs), leading to inconsistent results.

OBJECTIVE

This study synthesized available data from cohort studies to examine the effects of GWG on offspring CRFs.

DATA SOURCE

Four electronic databases, including PubMed, Web of Science, Scopus, and Embase, were searched through May 2023.

DATA EXTRACTION

Cohort studies evaluating the association between GWG and CRFs (fat mass [FM], body fat percentage [BF%], waist circumference [WC], systolic blood pressure [SBP] and diastolic blood pressure, high-density-lipoprotein cholesterol [HDL-C] and low-density-lipoprotein cholesterol, triglyceride [TG], total cholesterol, fasting blood glucose, and fasting insulin levels) were included. Regression coefficients, means or mean differences with 95% confidence intervals [CIs], or standard deviations were extracted.

DATA ANALYSIS

Thirty-three cohort studies were included in the meta-analysis. Higher GWG (per increase of 1 kg) was associated with greater offspring FM (0.041 kg; 95% CI, 0.016 to 0.067), BF% (0.145%; 95% CI, 0.116 to 0.174), WC (0.154 cm; 95% CI, 0.036 to 0.272), SBP (0.040 mmHg; 95% CI, 0.010 to 0.070), and TG (0.004 mmol/L; 95% CI, 0.001 to 0.007), and with lower HDL-C (-0.002 mmol/L; 95% CI, -0.004 to 0.000). Consistently, excessive GWG was associated with higher offspring FM, BF%, WC, and insulin, and inadequate GWG was associated with lower BF%, low-density lipoprotein cholesterol, total cholesterol, and TG, compared with adequate GWG. Most associations went non-significant or attenuated with adjustment for offspring body mass index or FM.

CONCLUSIONS

Higher maternal GWG is associated with increased offspring adiposity, SBP, TG, and insulin and decreased HDL-C in offspring, warranting a need to control GWG and to screen for cardiometabolic abnormalities of offspring born to mothers with excessive GWG.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023412098.

Association of gestational weight gain rate with infant birth weight and cesarean delivery: A prospective cohort study in Nepal

Gestational weight gain (GWG) is linked to pregnancy outcomes, such as birth weight and delivery mode, though research in low-income countries like Nepal is limited. We examined the association of GWG rate with infant birth weight and cesarean delivery in a prospective cohort of 191 pregnant women in Nepal, using data collected from August 2018 to August 2019 at a peri-urban hospital in Dhulikhel. Participants included women with singleton, full-term live births, with GWG rate calculated from weight gain between the second and late pregnancy stages, divided by the weeks in between. GWG rate categories-adequate, inadequate, or excessive-were defined by pre-pregnancy Body Mass Index (BMI) specific to GWG recommendations from the 2009 Institute of Medicine report. Ethical approval was obtained from Institutional Review Board of Kathmandu University and Rutgers University. Statistical analyses in SPSS and Stata revealed that 52.4% of mothers exceeded the recommended GWG rate, particularly among overweight and obese women (0.4 ± 0.2 kg/week and 0.5 ± 0.2 kg/week, respectively). The average birth weight was 2964.9 ± 407.0 grams, with 12% of infants classified as low-birth-weight. Cesarean delivery was recorded in 45% of the women. After controlling for factors like age, education, ethnicity, occupation, parity and BMI, each 1 kg/week increase in GWG from the second to third trimester correlated with a 392-gram increase in birth weight (β = 391.9, 95%CI = 67.2-716.7, p = 0.01), while excessive GWG rate led to a 148-gram increase over adequate GWG rate (β = 148.1, 95%CI = 8.7-287.5, p = 0.03). However, GWG rate was not significantly linked to cesarean delivery. These findings suggest that maternal GWG rate positively affects infant birth weight but not cesarean delivery, underscoring the need for larger studies to explore GWG rate's effects on maternal and neonatal outcomes.

Mediating role of gestational weight gain in the relationship between socioeconomic status and preterm birth: a Chinese population-based study

BACKGROUND

The modifiable mechanisms underlying the association between socioeconomic status (SES) and preterm birth remain unclear. This study aimed to investigate the relationship between preterm birth and maternal SES or gestational weight gain (GWG), as well as the role of GWG in mediating SES disparities in preterm birth.

METHODS

Data was from a hospital-based sub-study of physical growth and development survey for Chinese newborns with various gestational ages. Singleton newborns aged from 24 to 42weeks' gestation and their mothers were included. Using information from maternal questionnaire, a composite SES was constructed with parental education and family annual income. GWG as mediator was calculated by deducting pre-pregnancy weight from maternal weight at delivery. Logistic regression model was adopted to investigate the association of preterm birth with SES or GWG. Causal mediation analysis was performed to measure mediating effect of GWG on the pathway from SES to preterm birth.

RESULTS

After controlling for potential confounders, risk of preterm birth was reduced by 12.4% (OR = 0.876, 95%CI:0.855-0.879) for per one-kilogram increase of GWG, and risk of preterm birth was reduced by 24% (OR = 0.760, 95%CI: 0.717-0.806) for per one-unit increase of SES score. Mediation analysis supported a significant association between higher SES and decreased risk of preterm partly through higher GWG, in which estimated proportion mediated by GWG was 13.04% (95%CI: 11.89-16.25). GWG also played a significant role as a mediator when socioeconomic status was indicated by maternal education, paternal education or family income. GWG mediated approximately 11.03% (95% CI: 8.56-18.25) of the total effect of SES on very preterm birth, which was greater than that for moderate preterm birth (6.72%, 95%CI: 2.72-31.52) and late preterm birth (9.04%, 95%CI: 5.24-24.04). A series of sensitive analysis confirmed the robustness of association of interest.

CONCLUSION

Increased GWG and higher socioeconomic status are strongly associated with a lower risk of preterm birth. GWG mediates socioeconomic disparities in preterm birth, most notably in very preterm birth. Understanding this mechanism will aid in the development of interventions and policy for maternal and child health care.

Association between Gestational Weight Gain and Maternal and Birth Outcomes in Northern Ghana

Background

Although inappropriate gestational weight gain is considered closely related to adverse maternal and birth outcomes globally, little evidence was found in low- and middle-income countries. Study Objectives. This study is aimed at identifying the determinants of gestational weight gain and examine the association between gestational weight gain and maternal and birth outcomes in the Northern Region of Ghana. Study Methods. The study used a facility-based cross-sectional study design involving 611 antenatal and delivery records in Tatale district, Tamale west, and Gushegu municipal hospitals. A two-stage sampling method involving cluster and simple random sampling was employed. Descriptive statistical analysis and measures of central tendency were used to describe the sample. The multinomial logistic regression model was used to determine the determinants of gestational weight gain and its association with maternal and birth outcomes.

Results

Among the 611 women included in the study, 516 (84.45%) had inadequate gestational weight gain, and 19 (3.11%) had excessive gestational weight gain. The gestational weight gain ranged from 2 kg to 25 kg with a mean of 7.26 ± 3.70 kg. The risk factor for inadequate gestational weight gain was low prepregnancy BMI (adjusted odds ratio (AOR) = 1.33, 95% CI = 1.18 - 2.57, P = 0.002). Pregnant women who had inadequate gestational weight gain were significantly less likely to deliver through caesarean section (AOR = 0.27, 95% CI = 0.12 - 0.61, P = 0.002), and those who had excessive weight gain were more likely to undergo caesarean section (AOR = 19.81, 95% CI = 5.38 - 72.91, P = 0.001). The odds of premature delivery (birth < 37 weeks) among pregnant women with inadequate weight gain were 2.88 (95% CI = 1.27 - 6.50, P = 0.011). Furthermore, subjects who had excessive weight gain were 43.80 times more likely to give birth to babies with macrosomia (95% CI = 7.07 - 271.23, P = 0.001).

Conclusion

Inappropriate gestational weight gain is prevalent in Ghana, which is associated with caesarean section, preterm delivery, delivery complications, and macrosomia. Urgent policy interventions are needed to improve on the frequent monitoring and management of gestational weight gain of pregnant women till term.

Pre-pregnancy BMI, rate of gestational weight gain, and preterm birth among US Pacific Islander individuals

OBJECTIVE

The objective of this study was to examine the association between rate of gestational weight gain (GWG) and preterm birth (PTB) classified by pre-pregnancy BMI among Pacific Islander individuals in the United States.

METHODS

Pacific Islander mothers (n = 55,975) and singleton infants (22-41 gestational weeks) without congenital anomalies were included using data from the National Center for Health Statistics (2014-2018). PTB was compared by pre-pregnancy BMI among women in each stratum of rate of GWG using Cox proportional hazards models.

RESULTS

Compared with mothers with a rate of GWG within the guidelines, mothers with a rate of GWG below the guidelines and either pre-pregnancy underweight (adjusted hazard ratio [aHR] = 1.84, 95% CI: 1.10-3.06), healthy weight (aHR = 1.38, 95% CI: 1.15-1.65), obesity class I (aHR = 1.22, 95% CI: 0.97-1.52), or obesity class II (aHR = 1.43, 95% CI: 1.05-1.96) had an increased risk of PTB; mothers with a rate of GWG above the guidelines and either pre-pregnancy underweight (aHR = 1.57, 95% CI: 0.92-2.69) or obesity class II (aHR = 1.31, 95% CI: 0.98-1.76) had an increased risk of PTB.

CONCLUSIONS

The association between rate of GWG below or above the guidelines and PTB differs by pre-pregnancy BMI among Pacific Islander individuals.

Combined effects of pre-pregnancy BMI and gestational weight gain on preterm birth: comparison between spontaneous and ART conception

BACKGROUND

Inappropriate pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) are both linked to preterm birth (PTB); however, which one plays a dominant role in PTB risk is not yet sure. We aimed to evaluate the combined effect of pre-pregnancy BMI and GWG on the risk of PTB in singleton pregnancies conceived both spontaneously and through assisted reproductive technology (ART).

METHODS

The data included all mothers (n = 17,540,977) who had a live singleton birth from the US National Vital Statistics System (NVSS) 2015-2019. Logistic regression models, quantile-g-computation, and generalized additive model were used to analyze the combined association of pre-pregnancy BMI and GWG with PTB.

RESULTS

The singleton PTB rate was significantly higher in ART pregnancies (11.5%) than in non-ART pregnancies (7.9%). When compared to those women with pre-pregnancy normal weight and GWG within Institute of Medicine (IOM) guidelines, the highest PTB risk was observed in non-ART women with pre-pregnancy underweight and GWG below IOM guidelines (aOR 2.56; 95% CI 2.53-2.60) and in ART women with pre-pregnancy obese and GWG below IOM guidelines (aOR 2.56; 95%CI 2.36-2.78). GWG dominated the combined effect with its joint effect coefficient of - 0.281 (P < 0.05) in non-ART women and - 0.108 (P < 0.05) in ART women.

CONCLUSIONS

Inappropriate GWG played a dominant role in increasing the risk of PTB in both non-ART and ART populations. Counseling regarding pre-pregnancy BMI and especially GWG appears to be even more crucial for pregnancies conceived via ART, given their impact on PTB.

Gestational weight gain and its association with maternal and neonatal outcomes among pregnant women with normal pre-pregnancy body mass index from a Middle Eastern country

BACKGROUND

Inappropriate gestational weight gain (GWG) is one of the leading health problems during pregnancy. Little is known about the association of GWG with the pregnancy outcomes among Middle Eastern pregnant women.

PURPOSE

To examine the relationship between GWG and maternal and neonatal outcomes among pregnant women with normal pre-pregnancy BMI.

METHODS

This retrospective cohort study was conducted in Oman among 763 healthy women with normal pre-pregnancy BMI between August 1, 2021, and June 30, 2022. Maternal and neonatal outcomes were retrieved from participants' medical records using a standardized form. The analytical tools included descriptive statistics and the chi-square test.

RESULTS

Descriptive statistics showed 22.6 % and 21.4 % of the study participants gained weight above or below the guidelines, respectively. The findings from the chi-square test showed a significant association between total GWG and the incidence of emergency caesarean section (p < .01), gestational diabetes mellitus (p < .01), and gestational hypertension (p < .01), macrosomia (p < .01), small for gestational age (p < .01), large for gestational age (p < .01), low birth weight (p < .01), intrauterine growth retardation (p < .01), and preterm birth (p < .01).

CONCLUSION AND IMPLICATIONS FOR PRACTICE

Our study found that inappropriate gestational weight gain (GWG) contributes to several adverse maternal and neonatal outcomes. We recommend that Ministries of Health in Middle East and North Africa area includes GWG as a risk factor for pregnancy-related adverse outcomes. Midwives should closely monitor and manage GWG to ensure optimal pregnancy outcomes. In addition, midwives should encourage mothers to maintain GWG within the recommended range using various strategies such as continuous counselling and motivational health promotion interventions.

Eating Habits During Pregnancy of Women Giving Birth Very Prematurely: An Exploratory Analysis

INTRODUCTION

Preterm birth is increasing worldwide, representing a major cause of death and long-term loss of human potential among survivors. Some morbidities during pregnancy are well-known risk factors for preterm labor, but it is not yet known whether deviations from adequate dietary patterns are associated with preterm delivery. Diet may be an important modulator of chronic inflammation, and pro-inflammatory diets during pregnancy were reported to be associated with preterm birth. The aim of this study was to assess the food consumption during pregnancy of Portuguese women giving birth very prematurely and the association between the food consumption and the major maternal morbidities during pregnancy related with preterm delivery.

MATERIAL AND METHODS

A single-center cross-sectional observational study including consecutive Portuguese women giving birth before 33 weeks of gestation was conducted. Recall of eating habits during pregnancy was obtained within the first week after delivery, using a semi quantitative food frequency questionnaire validated for Portuguese pregnant women.

RESULTS

Sixty women with a median age of 36.0 years were included. Of these, 35% were obese or overweight at the beginning of pregnancy, 41.7% and 25.0% gained excessive or insufficient weight during pregnancy, respectively. Pregnancy-induced hypertension was present in 21.7% of cases, gestational diabetes in 18.3%, chronic hypertension in 6.7%, and type 2 diabetes mellitus in 5.0%. Pregnancy-induced hypertension was significantly associated with increased daily consumption of pastry products (31.2 vs 10.0 g, p = 0.022), fast food (39.6 vs 29.7 g, p = 0.028), bread (90.0 vs 50.0 g, p = 0.005), pasta, rice and potatoes (225.7 vs 154.3 g, p = 0.012). In a multivariate analysis, only bread consumption maintained a significant, albeit weak, association (OR = 1.021; 1.003 - 1.038, p = 0.022).

CONCLUSION

Pregnancy-induced hypertension was associated with increased consumption of pastry products, fast food, bread, pasta, rice, and potatoes, although only bread consumption had a weak but statistically significant association with pregnancy-induced hypertension in a multivariate analysis.

Polymorphisms in gene MTHFR modify the association between gestational weight gain and adverse birth outcomes

Evidence suggests a potential relationship between gestational weight gain (GWG) and adverse birth outcomes. However, the role of maternal genetic polymorphisms remains unclear. This study was conducted to investigate whether the relationship of GWG with risk of adverse birth outcomes was modified by methylenetetrahydrofolate reductase (MTHFR) polymorphisms. A total of 2,967 Chinese pregnant women were included and divided into insufficient, sufficient, and excessive groups based on the Institute of Medicine (IOM) criteria. Polymorphisms of C677T and A1298C in gene MTHFR were genotyped. Multivariable logistic regression models were introduced after controlling major confounders. Excessive GWG was found to increase the odds ratio (OR) for macrosomia [OR = 3.47, 95% confidence interval (CI): 1.86–6.48] and large-for-gestational age (LGA, OR = 3.25, 95% CI: 2.23–4.74), and decreased the OR for small-for-gestational age (SGA, OR = 0.60, 95% CI: 0.45–0.79). Pregnant women with insufficient GWG had a higher frequency of SGA (OR = 1.68, 95% CI: 1.32–2.13) and a lower rate of LGA (OR = 0.51, 95% CI: 0.27–0.96). Interestingly, significant associations of GWG categories in relation to low birth weight (LBW), macrosomia, and SGA were only suggested among pregnant women with MTHFR A1298C AA genotype. Among pregnant women with insufficient GWG group, an increased risk of 3.96 (95% CI: 1.57–10.01) for LBW was observed among subjects with the A1298C AA genotype, compared to the AC+CC genotype group. GWG categories are closely related to LBW, macrosomia, SGA and LGA, and the associations were modified by the polymorphism of MTHFR A1298C.

Pregnancy anxiety, placental corticotropin-releasing hormone and length of gestation

OBJECTIVE

High pregnancy anxiety is a consistent predictor of earlier labor and delivery. Placental corticotropin-releasing hormone (pCRH) predicts earlier delivery consistently and it has been identified as a biological mediator of the association between pregnancy anxiety and gestational length. However, studies have not examined whether changes in pregnancy anxiety are associated with earlier birth as mediated by changes in pCRH during pregnancy. Accordingly, this study tests whether linear changes in pregnancy anxiety are associated with length of gestation indirectly through nonlinear increases in pCRH over pregnancy.

METHODS

A sample of pregnant women (n=233) completed prenatal assessments in early pregnancy, second trimester, and third trimester that included a 4-item assessment of pregnancy anxiety and collection of blood samples assayed for pCRH using radioimmunoassay. Length of gestation was abstracted from medical records after birth.

RESULTS

Increases in pregnancy anxiety from early pregnancy to third trimester predicted shorted length of gestation, as did nonlinear increases in pCRH over pregnancy. However, there was no evidence of an indirect effect of changes in pregnancy anxiety on length of gestation via changes in pCRH.

CONCLUSIONS

These results indicate that linear changes in pregnancy anxiety and nonlinear changes in pCRH during pregnancy are independent risk factors for shortened gestational length. This study adds to a small but growing body of work on biopsychological processes in pregnancy and length of gestation. Modeling changes in psychological and biological processes during pregnancy could provide more insight into understanding risk for adverse pregnancy outcomes.

Gestational weight gain during the second and third trimesters and adverse pregnancy outcomes, results from a prospective pregnancy cohort in urban Tanzania

BACKGROUND

Appropriate gestational weight gain (GWG) is important for optimal pregnancy outcomes. This study prospectively evaluated the associations between GWG during the second and third trimesters of pregnancy and adverse pregnancy outcomes in an urban Tanzanian pregnancy cohort.

METHODS

We used data from a randomized clinical trial conducted among pregnant women recruited by 27 weeks of gestation in Dar es Salaam, Tanzania (N = 1230). Women's gestational weight was measured at baseline and at monthly antenatal visits. Weekly GWG rate during the second and third trimesters was calculated and characterized as inadequate, adequate, or excessive, in conjunction with measured or imputed early-pregnancy BMI status according to the 2009 Institute of Medicine (IOM) GWG guidelines. We used multivariable Poisson regression with a sandwich variance estimator to calculate risk ratios (RR) for associations of GWG with low birth weight, preterm birth, small for gestational age (SGA), and large for gestational age (LGA). Degree of appropriate GWG defined using additional metrics (i.e., percentage of adequacy, z-score) and potential effect modification by maternal BMI were additionally evaluated.

RESULTS

According to the IOM guidelines, 517 (42.0%), 270 (22.0%), and 443 (36.0%) women were characterized as having inadequate, adequate, and excessive GWG, respectively. Overall, compared to women with adequate GWG, women with inadequate GWG had a lower risk of LGA births (RR = 0.54, 95% CI: 0.36-0.80) and a higher risk of SGA births (RR = 1.32, 95% CI: 0.95-1.81). Women with inadequate GWG as defined by percentage of GWG adequacy had a higher risk of LBW (OR = 1.93, 95% CI: 1.03-3.63). In stratified analyses by early-pregnancy BMI, excessive GWG among women with normal BMI was associated with a higher risk of preterm birth (RR = 1.59, 95% CI: 1.03-2.44).

CONCLUSIONS

A comparatively high percentage of excessive GWG was observed among healthy pregnant women in Tanzania. Both inadequate and excessive GWGs were associated with elevated risks of poor pregnancy outcomes. Future studies among diverse SSA populations are warranted to confirm our findings, and clinical recommendations on optimal GWG should be developed to promote healthy GWG in SSA settings.

TRIAL REGISTRATION

This trial was registered as "Prenatal Iron Supplements: Safety and Efficacy in Tanzania" (NCT01119612; http://clinicaltrials.gov/show/NCT01119612 ).

Preventive Counseling in Routine Prenatal Care-A Qualitative Study of Pregnant Women's Perspectives on a Lifestyle Intervention, Contrasted with the Experiences of Healthcare Providers

Maternal lifestyle during pregnancy and excessive gestational weight gain can influence maternal and infant short and long-term health. As part of the GeMuKi intervention, gynecologists and midwives provide lifestyle counseling to pregnant women during routine check-up visits. This study aims to understand the needs and experiences of participating pregnant women and to what extent their perspectives correspond to the experiences of healthcare providers. Semi-structured interviews were conducted with 12 pregnant women and 13 multi-professional healthcare providers, and were analyzed using qualitative content analysis. All interviewees rated routine check-up visits as a good setting in which to focus on lifestyle topics. Women in their first pregnancies had a great need to talk about lifestyle topics. None of the participants were aware of the link between gestational weight gain and maternal and infant health. The healthcare providers interviewed attributed varying relevance regarding the issue of weight gain and, accordingly, provided inconsistent counseling. The pregnant women expressed dissatisfaction regarding the multi-professional collaboration. The results demonstrate a need for strategies to improve multi-professional collaboration. In addition, health care providers should be trained to use sensitive techniques to inform pregnant women about the link between gestational weight gain and maternal and infant health.

Effectiveness of a Brief Lifestyle Intervention in the Prenatal Care Setting to Prevent Excessive Gestational Weight Gain and Improve Maternal and Infant Health Outcomes

Research on perinatal programming shows that excessive gestational weight gain (GWG) increases the risk of overweight and obesity later in a child’s life and contributes to maternal weight retention and elevated risks of obstetrical complications. This study examined the effectiveness of a brief lifestyle intervention in the prenatal care setting, compared to routine prenatal care, in preventing excessive GWG as well as adverse maternal and infant health outcomes. The GeMuKi study was designed as a cluster RCT using a hybrid effectiveness implementation design and was conducted in the prenatal care setting in Germany. A total of 1466 pregnant women were recruited. Pregnant women in intervention regions received up to six brief counseling sessions on lifestyle topics (e.g., physical activity, nutrition, drug use). Data on GWG and maternal and infant outcomes were entered into a digital data platform by the respective healthcare providers. The intervention resulted in a significant reduction in the proportion of women with excessive GWG (OR = 0.76, 95% CI (0.60 to 0.96), p = 0.024). Gestational weight gain in the intervention group was reduced by 1 kg (95% CI (−1.56 to −0.38), p < 0.001). No evidence of intervention effects on pregnancy, birth, or neonatal outcomes was found.

Associations of Gestational Diabetes Mellitus and Excessive Gestational Weight Gain with Offspring Obesity Risk

OBJECTIVE

Gestational diabetes mellitus (GDM) and gestational weight gain (GWG) are important risk factors that are known to affect offspring growth, but these outcomes are inconsistent and it remains unknown if both risk factors have a synergetic effect on early childhood growth. The present study aimed to conduct offspring body mass index-for-age Z-scores (BMIZ) trajectories and to evaluate the independent and interactive effect of the status of GDM and excessive GWG on the risks of overweight/obesity from birth to 24 months of age.

METHODS

A total of 7949 mother-child pairs were enrolled in this study. The weight and length of children were measured at birth, 6, 12, and 24 months of age to calculate BMIZ.

RESULTS

The status of GDM was positively associated with offspring BMIZ and risk of macrosomia at birth but was not associated with offspring BMIZ or the risks of overweight/obesity at 6, 12, and 24 months of age. In contrast, excessive GWG was positively linked to offspring BMIZ, the stable high BMIZ trajectory pattern, and risks of overweight/obesity in the first 24 months of age. These two risk factors also had a significant synergistic effect on macrosomia at birth, but the interactive effect was only significant in boys during the follow-up years in the sex-stratified analyses.

CONCLUSION

The maternal GWG was a more pronounced predictor than GDM with relation to BMIZ and risk of overweight/obesity in early childhood. The interactive effect between these risk factors on offspring overweight/obesity may vary by sex.

Effect of individualized weight management intervention on excessive gestational weight gain and perinatal outcomes: a randomized controlled trial

It is unclear whether weight management is still effective for pregnant women with excessive weight gain in the second or third trimester in China. This study adopted individualized weight management intervention for pregnant women with abnormal weight gain in the second or third trimester, to analyze the effect of intervention by observing the gestational weight gain and perinatal outcomes. This randomized controlled trial was performed at Aerospace Center Hospital. The obstetrician determined whether the pregnant women gained too much weight in the second or third trimester according to the Institute of Medicine guidelines, and randomly divided the pregnant women who gained too much weight in the second or third trimester into the intervention group or the control group according to the inclusion and exclusion criteria. The pregnant women in the intervention group and in the control group all received routine prenatal examination and diet nutrition education by the doctors in the Department of Obstetrics and Gynecology. The intervention group underwent individualized weight management, including individualized diet, exercise, psychological assessment, cognitive intervention and continuous communication, the whole process is tracked and managed by professional nutritionists. The obstetrician collected the prenatal examination data and pregnancy outcome data of all enrolled pregnant women. The primary outcome measure was weight gain during pregnancy. A generalized linear model and a logistic regression model were used to compare the outcomes between the two groups. In total, 348 pregnant women participated in this study with 203 in the intervention group and 145 in the control group. The whole gestational weight gain in the intervention group (15.8 ± 5.4 Kg) was lower than that in the control group (17.5 ± 3.6 Kg; adjusted β =  - 1.644; 95% CI [-2.660--0.627]; P = 0.002). The percent of pregnant women with excessive weight gainbefore delivery was 54.2% (110/203) in the intervention group, which was lower than 69.7% (101/145) in the control group (adjusted RR = 0.468; 95% CI [0.284-0.769] P = 0.003). The pregnant women given the individualized weight management intervention from the second to the third trimester experienced less weight gain than that from the third trimester (15.5 ± 5.6 Kg vs. 16.2 ± 5.2 Kg), but without significant difference (P = 0.338). Lower rates of GDM, preeclampsia and gestational hypertension, higher rates of fetal distress and puerperal infection were observed in the intervention group than in the control group (all P < 0.05). Individualized weight management during the second or third trimesters is still beneficial for pregnant women who gain excessive weight and can decrease the associated adverse outcomes.

Impact of maternal pre-pregnancy body mass index on maternal, fetal and neonatal adverse outcomes in the worldwide populations: A systematic review and meta-analysis

OBJECTIVE

Systematic review and meta-analysis conducted to investigate the effect of stratified pre-pregnancy maternal body mass index on twenty maternal and fetal/neonatal adverse outcomes.

METHODS

PubMed, Google Scholar, Medline, Embase, Web of Science databases were searched from inception till July 11, 2020. Cohort studies were included. The pooled odds ratio with 95% confidence interval was reported considering the random effect and the quality effect model. The sub-group analysis and meta-regression were conducted for BMI cut-offs, geographical region, source of BMI, and sample size.

RESULTS

Overall, 86 studies representing 20,328,777 pregnant women were included in this meta-analysis. Our study reveals that overweight and obese mothers are at increased odds of cesarean delivery, elective cesarean delivery, emergency cesarean delivery, gestational diabetes, gestational hypertension, induction of labor, postpartum hemorrhage, pre-eclampsia, pre-term premature rupture of membrane, and the fetuses/neonates of overweight and obese mothers are at increased risk of admission in the newborn intensive care unit, APGAR scores less than 7 at 5 min, large for gestational age, macrosomia, extreme pre-term birth in pregnant mothers compared with standard BMI mothers. However, the underweight mothers showed increased odds for small for gestational age infant and pre-term birth, whereas obese mothers were at higher risk for post-term birth and stillbirths. The subgroup and meta-regression analyses have shown the impact of BMI cut-offs, geographical region, source of BMI, and sample size on several maternal, fetal/neonatal adverse outcomes.

CONCLUSION

The meta-analysis confirmed the association of elevated pre-pregnancy maternal BMI with higher odds of adverse maternal and fetal/neonatal outcomes.

Pre-conception and prenatal factors influencing gestational weight gain: a prospective study in Tigray region, northern Ethiopia

Background

In low-income countries, the high prevalence of pre-pregnancy undernutrition remains a challenge for the future health of women and their offspring. On top of good nutrition, adequate gestational weight gain has been recognized as an essential prerequisite for optimal maternal and child health outcomes. However, good-quality data on factors influencing gestational weight gain is lacking. Therefore, this study was aimed to prospectively identify pre-conception and prenatal factors influencing gestational weight gain in Ethiopia.

Methods

A population based prospective study was undertaken between February 2018 and January 2019 in the Tigray region, northern Ethiopia. Firstly, the weight of non-pregnant women of reproductive age living in the study area was measured between August and October 2017. Subsequently, eligible pregnant women identified during the study period were included consecutively and followed until birth. Data were collected through an interviewer-administered questionnaire and anthropometric measurements complemented with secondary data. Gestational weight gain, i.e., the difference between 32 to 36 weeks of gestation and pre-pregnancy weights, was classified as per the Institute of Medicine (IOM) guideline. Linear, spline, and logistic regression models were used to estimate the influence of pre-conception and prenatal factors on gestational weight gain.

Results

The mean gestational weight gain (standard deviation[SD]) was 10.6 (2.3) kg. Overall, 64.0% (95% CI 60.9, 67.1) of the women did not achieve adequate weight gain. Factors associated with higher gestational weight gain were higher women empowerment (B 0.60, 95% CI 0.06, 1.14), dietary diversity (B 0.39, 95% CI 0.03, 0.76), pre-pregnancy body mass index (B 0.13, 95% CI 0.05, 0.22), and haemoglobin (B 0.54, 95% CI 0.45, 0.64). Additionally, adequate prenatal care (B 0.58, 95% CI 0.28, 0.88) was associated with higher gestational weight gain.

Conclusions

Adequate gestational weight gain was not achieved by most women in the study area, primarily not by those who were underweight before pregnancy. Interventions that advance women’s empowerment, dietary quality, pre-pregnancy nutritional status, and prenatal care utilization may improve gestational weight gain and contribute to optimizing maternal and child health outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04171-z.

Serum lipid levels in relation to clinical outcomes in pregnant women with gestational diabetes mellitus: an observational cohort study

BACKGROUND

Research on dyslipidemia during pregnancy in women with gestational diabetes mellitus (GDM) has rarely been conducted in Asia. The present study aimed to evaluate maternal mid-trimester lipid profile in relation to GDM and clinical outcomes in these high-risk populations.

METHODS

The medical records of 632 pregnant women in the second trimester were retrospectively analyzed. Maternal fasting serum lipids were assayed for total cholesterol (TC), triglycerides (TG), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), apolipoprotein A1 (Apo A1) and Apo B concentrations during the second trimester. The atherogenic index of plasma (AIP) was calculated as log (TG/HDL). The clinical outcomes were collected by evaluating delivery mode, postpartum hemorrhage, prematurity, macrosomia, birth weight, body length and neonatal Apgar 5 min score.

RESULTS

Levels of TG and AIP were elevated while decreased HDL-C was observed in women with GDM compared with that of the control group. Significant differences were observed in gestational weeks at birth, cesarean section, postpartum hemorrhage, birth weight, body length, prematurity and macrosomia between the two groups. Compared with women with hyperlipidemia, the incidence of GDM and cesarean section was lower in normal lipid group. Women in the hyperlipidemia group had smaller gestational weeks at birth than those in the control group. According to the logistic regression analysis, each unit elevation in AIP increased the risk of GDM by 18.48 times (OR = 18.48, CI: 2.38-143.22). Besides, age (OR = 1.11, CI: 1.06-1.16) and pre-pregnancy BMI (OR = 1.15, CI: 1.07-1.24) were the risk factors of GDM.

CONCLUSIONS

These findings suggested that reasonable lipid control in the second trimester might reduce the incidence of GDM and be a potential strategy for improving clinical outcomes in these high-risk women.

Prepregnancy Obesity Does Not Impact Placental Iron Trafficking

BACKGROUND

Iron is critical for fetal development. Neonates of obese women may be at risk for poor iron status at birth as a result of maternal inflammation-driven overexpression of hepcidin.

OBJECTIVES

The objective of this study was to determine differences in placental transfer of oral iron (57Fe) and expression of placental transferrin receptor 1 (TFR1) and ferroportin (FPN) mRNA and protein and their association with maternal and neonatal iron-related parameters, including maternal hepcidin, among women with and without prepregnancy (PP) obesity.

METHODS

57Fe ingested during the third trimester of pregnancy was recovered in venous umbilical cord blood among 20 PP obese [BMI (in kg/m2): 30.5-43.9] and 22 nonobese (BMI: 18.5-29.0) women aged 17-39 y. Placental TFR1 and FPN mRNA and protein expression were quantified via qPCR and Western blot. Maternal and neonatal markers of iron status and regulation, as well as inflammation, were measured. Descriptive and inferential statistical tests (e.g., Student t test, Pearson correlation) were used for data analysis.

RESULTS

There was no difference in cord blood enrichment of 57Fe or placental mRNA or protein expression of TFR1 or FPN among the women with and without PP obesity. Maternal hepcidin was not correlated with cord blood enrichment of 57Fe or placental FPN mRNA or protein expression. Maternal log ferritin (corrected for inflammation) was inversely correlated with log percent enrichment of 57Fe in cord blood (partial r = -0.50; P < 0.01, controlled for marital status) and protein expression of TFR1 (r = -0.43; P = 0.01).

CONCLUSIONS

Placental iron trafficking did not differ among women with and without PP obesity. Findings reinforce the importance of maternal iron stores in regulating placental iron trafficking.

Association between gestational weight gain in women with gestational diabetes mellitus and adverse pregnancy outcomes: a retrospective cohort study

Background

To examine association between gestational weight gain (GWG) in women with gestational diabetes mellitus (GDM) and adverse pregnancy outcomes (APOs).

Methods

This retrospective cohort study enrolled women with GDM who delivered at 2010–2020 in Changzhou, Jiangsu. Total GWG, rates of GWG in second trimester and third trimesters were stratified into three categories according to IOM guidelines: within, below, and above IOM guidelines. Univariable and multivariable logistic regression analyses were used.

Results

Overall, 1606 women with GDM fulfilled inclusion criteria. Compared with within IOM guidelines and after adjusting for confounders, total GWG above IOM guidelines in pregnancy was associated with an increased odds of caesarean delivery [adjusted odds ratio (aOR) = 1.34, 95% confidence interval (CI): 1.04–1.72], hypertensive disorders of pregnancy (HDP) (aOR = 2.00, 1.28–3.12), preeclampsia (aOR = 2.06, 1.01–3.12), macrosomia (aOR = 1.55, 1.13–2.13) and large for gestational age (LGA) (aOR = 2.82, 1.94–3.23), and a decreased odds of premature rupture of membrane (PROM) (aOR = 0.46, 0.36–0.60) and preterm birth (aOR = 0.35, 0.26–0.44); total GWG below IOM guidelines in pregnancy was associated with an increased risk of preterm birth (aOR = 1.96, 1.44–2.66), small for gestational age (SGA) (aOR = 1.32, 1.11–1.50) and a decreased odds of macrosomia (aOR = 0.35, 0.23–0.53) and LGA (aOR = 0.54, 0.42–0.72). Further, in both second and third trimesters of pregnancy, rates of GWG above IOM guidelines was found to be associated with a high odds of HDP (aOR = 2.55, 1.86–3.38; aOR = 1.93, 1.08–2.98), preeclampsia (aOR = 2.28, 1.21–3.81; aOR = 2.17, 1.35–4.37), macrosomia (aOR = 1.20, 1.02–1.82; aOR = 2.02, 1.51–2.64) and LGA (aOR = 1.42, 1.24–1.97; aOR = 1.79, 1.51–2.54). Rates of GWG above IOM guidelines in third trimester of pregnancy also increased odds of caesarean delivery (aOR = 1.48, 1.16–2.34) when compared with within IOM guidelines. While rates of GWG below IOM guidelines in both second and third trimesters of pregnancy was associated with a decreased odds of macrosomia (aOR = 0.66, 95% CI: 0.52–0.78; aOR = 0.52, 0.39–0.63) and LGA(aOR = 0.71, 0.51–0.82; aOR = 0.67, 0.55–0.79). In addition, rate of GWG below IOM guidelines in third trimester of pregnancy was associated with an increased odds of preterm birth (aOR = 1.52, 1.12–2.05) and SGA (aOR = 1.21, 1.10–1.69).

Conclusion

GWG, outside IOM guidelines has increased risks of APOs among women with GDM, implying that careful surveillance for GWG during different stages of pregnancy is warranted.

Institute of Medicine Recommendations on the Rate of Gestational Weight Gain and Perinatal Outcomes in Rural Bangladesh

Although validated in other parts of the world, the suitability of the U.S. Institute of Medicine (IOM) 2009 recommendations on gestational weight gain (GWG) for Bangladeshi women remains to be examined. We evaluated the association between the weekly rate of weight gain during the second and third trimester of pregnancy, categorized according to IOM recommendations, and adverse perinatal outcomes among 1569 pregnant women with singleton live births in rural Matlab, Bangladesh. Gaining weight at rates below the IOM recommendations was associated with higher odds of preterm birth (adjusted odds ratio (AOR) = 2.0, 95% CI: 1.1-3.6), low birth weight (AOR = 1.4, 95% CI: 1.03-2.0), small-for-gestational-age newborns (AOR = 1.3, 95% CI: 1.04-1.7), and poor neonatal outcome (severe neonatal morbidity or death, AOR = 2.4, 95% CI: 1.03-5.6). A GWG rate above the recommendations was associated with higher odds of cesarean delivery (AOR = 1.7, 95% CI: 1.1-2.6), preterm birth (AOR = 2.2, 95% CI: 1.1-4.4), large-for-gestational-age newborns (AOR = 5.9, 95% CI: 1.5-23.1), and poor neonatal outcome (AOR = 2.7, 95% CI: 1.04-7.0). Our results suggest that the IOM 2009 recommendations on GWG rate during the second and third trimester may be suitable for guiding rural Bangladeshi women in the prenatal period, although the women should aim for rates near the lower bound of the range.

[Effect of Lifestyle Intervention Program for Overweight and Obesity Pregnant Women]

PURPOSE

This study was conducted to identify the effects of a lifestyle intervention program on weight gain, dietary habits, fatigue and pregnancy stress, blood pressure, and neonatal birth weight, using Cox's interaction model of client health behavior for overweight and obese women.

METHODS

This was a quasi-experimental research with a non-equivalent control group pre-post test design. A total of 52 patients who met the selection criteria, including 25 in the experimental group and 27 in the control group, were the subjects of the study; they comprised overweight and obese pregnant women who were receiving prenatal care at A and B women's hospital in J province. The lifestyle intervention program ran for 12 weeks in total and consisted of interactions involving affective support, health information, and professional/technical competencies. The data collection period was from February 1, 2017 to August 31, 2017.

RESULTS

This study showed differences in the appropriate weight gain rate (χ²=6.17, p=.013), suppression of an increase in fatigue (t=-2.32, p=.012), and an increase in pregnancy stress (t=-1.87, p=.034). Yet, no differences in physical activity, dietary habits change, blood pressure, and neonatal birth weight (p>.05) were found.

CONCLUSION

The study findings indicate that this program could be an effective intervention for the control of appropriate weight gain, fatigue, and pregnancy stress. Therefore, a lifestyle intervention program based on Cox's interaction model of client health behavior could be an efficient strategy for a positive health outcome of overweight and obesity pregnant women.

Optimal gestational weight gain in Chinese pregnant women by Chinese-specific BMI categories: a multicentre prospective cohort study

OBJECTIVE

To establish optimal gestational weight gain (GWG) in Chinese pregnant women by Chinese-specific BMI categories and compare the new recommendations with the Institute of Medicine (IOM) 2009 guidelines.

DESIGN

Multicentre, prospective cohort study. Unconditional logistic regression analysis was used to evaluate the OR, 95 % CI and the predicted probabilities of adverse pregnancy outcomes. The optimal GWG range was defined as the range that did not exceed a 1 % increase from the lowest predicted probability in each pre-pregnancy BMI group.

SETTING

From nine cities in mainland China.

PARTICIPANTS

A total of 3731 women with singleton pregnancy were recruited from April 2013 to December 2014.

RESULTS

The optimal GWG (ranges) by Chinese-specific BMI was 15·0 (12·8-17·1), 14·2 (12·1-16·4) and 12·6 (10·4-14·9) kg for underweight, normal weight and overweight pregnant women, respectively. Inappropriate GWG was associated with several adverse pregnancy outcomes. Compared with women gaining weight within our proposed recommendations, women with excessive GWG had higher risk for macrosomia, large for gestational age and caesarean section, whereas those with inadequate GWG had higher risk for low birth weight, small for gestational age and preterm delivery. The comparison between our proposed recommendations and IOM 2009 guidelines showed that our recommendations were comparable with the IOM 2009 guidelines and could well predict the risk of several adverse pregnancy outcomes.

CONCLUSIONS

Inappropriate GWG was associated with higher risk of several adverse pregnancy outcomes. Optimal GWG recommendations proposed in the present study could be applied to Chinese pregnant women.

WeChat-assisted dietary and exercise intervention for prevention of gestational diabetes mellitus in overweight/obese pregnant women: a two-arm randomized clinical trial

PURPOSE

This study aimed to examine the influence of a WeChat-based dietary and exercise intervention on gestational diabetes mellitus (GDM) prevention in overweight/obese pregnant women in Beijing.

METHODS

Overweight/obese pregnant women were recruited in the early stages of pregnancy. After screening by include and exclude standards, eligible women were randomly divided into two groups, intervention and control groups. The control group received a general advice session about pregnancy nutrition and weight management. The intervention group received three face-to-face sessions about personalized dietary and exercise intervention, with the help of WeChat as a monitoring tool to promote treatment plan adherence. At 24-28 weeks of pregnancy, GDM was diagnosed according to the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria. Gestational weight gain (GWG), maternal and neonatal outcomes were also collected.

RESULTS

This study analyzed 215 participants. At the mid-trimester, 42 (37.8%) women in the control group were diagnosed with GDM (n = 111) versus 25 (24.5%) in the intervention group (n = 104; p < 0.05). The intervention group gained 11.2 ± 4.9 kg during the whole gestation period, with 4.9 ± 3.1 kg-weight increment in the first 25 weeks of pregnancy, versus 13.4 ± 5.0 kg and 6.9 ± 3.2 kg in the first 25 weeks in the control group (between groups: p < 0.001/p = 0.002). Incidence of macrosomia was not significantly lower in the intervention group than in the control group (8/7.9% vs 11/9.9%) (p > 0.05). No significant difference was found in the rate of natural labor and occurrence of perinatal complications (e.g., preterm birth, gestational hypertension, and preeclampsia) between the groups (p > 0.05).

CONCLUSIONS

The WeChat-assisted dietary and exercise intervention was effective in reducing the occurrence of GDM and excessive weight gain in overweight/obese pregnant women. Disseminating knowledge of pregnancy and childbirth through social media platforms like WeChat could be an important part of antenatal care.

Association among pre-pregnancy body mass index, gestational weight gain and neonatal birth weight: a prospective cohort study in China

Background

This study aims to explore the relationships between pre-pregnancy body mass index (BMI), gestational weight gain (GWG), rate of GWG during the second and third trimesters (GWG_rate) and birth weight among Chinese women.

Methods

Women were enrolled by 24 hospitals in 15 different provinces in mainland China from July 25th, 2017 to 26 November 2018. Pre-pregnancy BMI, GWG and GWG_rate were calculated and divided in to different groups. The multinomial logistic regression model and restrictive cubic spline model were used to explore the relationships.

Results

Of the 3585 participants, women who were underweight, had insufficient GWG or GWG_rate had 1.853-, 1850- or 1.524-fold higher risks for delivering small-for-gestational-age (SGA) infant compared with women who had normal BMI, sufficient GWG or GWG_rate. Women who were overweight/obese, had excessive GWG or GWG_rate had 1.996-, 1676- or 1.673-fold higher risks for delivering large-for-gestational-age (LGA) infant. The effects of GWG and GWG_rate on birth weight varied by pre-pregnancy BMI statuses. Dose-response analysis demonstrated L-shaped and S-shaped relationships between pre-pregnancy BMI, GWG, GWG_rate and neonatal birth weight.

Conclusions

Pre-pregnancy BMI, GWG or GWG_rate were associated with neonatal birth weight among Chinese women. Both body weight before and during pregnancy should be maintained within the recommendations to prevent abnormal birth weight.

Gestational weight gain in twin pregnancies in Korea: application of the 2009 Institute of Medicine recommendations

Objective

To investigate the effect of gestational weight gain (GWG) on maternal and neonatal outcomes based on the Institute of Medicine (IOM) guidelines for twin pregnancies.

Methods

This study included women with twin pregnancies who delivered at Seoul National University Bundang Hospital. Based on the weight gain per gestational week according to the 2009 IOM guidelines, the subjects were divided into the following 3 groups: inadequate, adequate, and excessive GWG. We compared the maternal and neonatal outcomes of each group.

Results

A total of 1,738 twin pregnancies were included in our study. Of these cases, 881, 694, and 163 (50.7%, 39.9%, and 9.4%, respectively) twin pregnancies were categorized into the inadequate, adequate, and excessive GWG groups, respectively. In the inadequate GWG group, the risks of preterm birth <34 weeks (aOR, 2.33, 95% confidence interval [CI], 1.63–3.34) and delivering neonates who were small for gestational age (aOR, 1.92, 95% CI, 1.42–2.60) were increased, and the risk of preeclampsia (aOR, 0.49, 95% CI, 0.32–0.76) was decreased. The excessive GWG group had an increased risk of the neonates being large for gestational age (aOR, 1.79, 95% CI, 1.15–2.81).

Conclusion

The 2009 IOM recommendations for GWG can be applied to Korean women with twin pregnancies to help achieve optimal maternal and neonatal outcomes. However, more than half of the women were categorized as having inadequate weight gain according to the guidelines. Further studies should be performed to obtain Korean national references for GWG in twin pregnancies.

Associations between gestational weight gain and preterm birth in Puerto Rico

BACKGROUND

Preterm birth (PTB; gestational age < 37 weeks) is the leading cause of infant morbidity and mortality worldwide. Low and excessive gestational weight gain (GWG) have been previously cited as risk factors for PTB, however the magnitude of association varies across populations. No studies have examined low and excessive GWG as modifiable risk factors for PTB in Puerto Rico, an area with inexplicably high PTB rates.

METHODS

To examine the relationship between GWG and PTB, we conducted a retrospective analysis using birth certificate data files from the Puerto Rico Department of Health from 2005 to 2012. GWG was standardized to a 40-week gestational duration and was categorized into low, adequate, or excessive for each category of pre-pregnancy body mass index using American College of Obstetricians and Gynecologists guidelines. Logistic regression was used to determine the crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) for the association between GWG and PTB.

RESULTS

There were 320,695 births included in this analysis; 40.6% with high GWG and 27.3% with low GWG. A greater percentage of women with low GWG were less than 20 years of age, had less than a high school education, and were underweight compared to women with adequate and excessive GWG. Women with low compared to adequate GWG had increased odds of PTB (OR = 1.34, 95% CI = 1.30-1.37). However, excessive compared to adequate GWG was not associated with PTB (OR = 0.99, 95% CI = 0.97-1.02).

CONCLUSIONS

Among women in Puerto Rico, low GWG was associated with increased odds of PTB. With the exception of obesity, these associations persisted within all strata of pre-pregnancy body mass index, highlighting the importance of maintaining a healthy weight during pregnancy. Future research should examine other factors that may contribute to GWG, such as dietary nutrients, and explore pathways through which GWG may be contributing to PTB.

Exposure to Community Homicide During Pregnancy and Adverse Birth Outcomes: A Within-Community Matched Design

BACKGROUND

Community violence is an understudied aspect of social context that may affect risk of preterm birth and small-for-gestational age (SGA).

METHODS

We matched California mothers with live singleton births who were exposed to a homicide in their Census tract of residence in 2007-2011 to unexposed mothers within the same tract. We estimated risk differences with a weighted linear probability model, with weights corresponding to the matched data structure. We estimated the average treatment effect on the treated of homicide exposure on the risk of preterm birth and SGA during the preconception period and first and second trimester.

RESULTS

We found a small increase in risk of SGA associated with homicide exposure in the first trimester (0.14% [95% confidence interval (CI) = -0.01%, 0.30%]), but not for exposure during the preconception period (-0.01% [95% CI = -0.17%, 0.15%]) or the second trimester (-0.06% [95% CI = -0.23%, 0.11%]). Risk of preterm birth was not affected by homicide exposure. When women were exposed to homicides during all three exposure windows, there was a larger increase in risk of SGA (1.09% [95% CI = 0.15%, 2.03%]) but not preterm birth (0.14% [95% CI = -0.74%, 1.01%]). Exposure to three or more homicides was also associated with greater risk of SGA (0.78% [95% CI = 0.15%, 1.40%]). Negative controls indicated that residual confounding by temporal patterning was unlikely.

CONCLUSIONS

Homicide exposure during early pregnancy is associated with a small increased risk of SGA.

Rate of gestational weight gain trajectory is associated with adverse pregnancy outcomes

OBJECTIVE

To examine the gestational weight gain (GWG) trajectory and its possible association with pregnancy outcomes.

DESIGN

GWG trajectories were identified using the latent class growth model. Binary logistic regression was performed to examine the associations between adverse pregnancy outcomes and these trajectories.

SETTING

Negeri Sembilan, Malaysia.

PARTICIPANTS

Two thousand one hundred ninety-three pregnant women.

RESULTS

Three GWG trajectories were identified: 'Group 1 - slow initial GWG but followed by drastic GWG', 'Group 2 - maintaining rate of GWG at 0·58 kg/week' and 'Group 3 - maintaining rate of GWG at 0·38 kg/week'. Group 1 had higher risk of postpartum weight retention (PWR) (adjusted OR (AOR) 1·02, 95 % CI 1·01, 1·04), caesarean delivery (AOR 1·03, 95 % CI 1·01, 1·04) and having low birth weight (AOR 1·04, 95 % CI 1·02, 1·05) compared with group 3. Group 2 was at higher risk of PWR (AOR 1·18, 95 % CI 1·16, 1·21), preterm delivery (AOR 1·03, 95 % CI 1·01, 1·05) and caesarean delivery (AOR 1·02, 95 % CI 1·01, 1·03), but at lower risk of having small-for-gestational-age infants (AOR 0·97, 95 % CI 0·96, 0·99) compared with group 3. The significant associations between group 1 and PWR were observed among non-overweight/obese women; between group 1 and caesarean delivery among overweight/obese women; group 2 with preterm delivery and caesarean delivery were only found among overweight/obese women.

CONCLUSIONS

Higher GWG as well as increasing GWG trajectories was associated with higher risk of adverse pregnancy outcomes. Promoting GWG within the recommended range should be emphasised in antenatal care to prevent the risk of adverse pregnancy outcomes.

Maternal genitourinary infections and poor nutritional status increase risk of preterm birth in Gasabo District, Rwanda: a prospective, longitudinal, cohort study

BACKGROUND

Preterm birth (PTB) is a leading cause of early childhood mortality and morbidity, including long-term physical and mental impairment. The risk factors for PTB are complex and include maternal nutritional status and infections. This study aimed to identify potentially modifiable risk factors for targeted interventions to reduce the occurrence of PTB in Rwanda.

METHODS

We conducted a prospective, longitudinal cohort study of healthy pregnant women aged 18 to 49 years. Women at 9-15 gestational weeks were recruited from 10 health centers in Gasabo District, Kigali Province between September and October 2017. Pregnancy age was estimated using ultrasonography and date of last menstruation. Anthropometric and laboratory measurements were performed using standard procedures for both mothers and newborns. Surveys were administered to assess demographic and health histories. Categorical and continuous variables were depicted as proportions and means, respectively. Variables with p <  0.25 in bivariate analyses were included in multivariable logistic regression models to determine independent predictors of PTB. The results were reported as odds ratios (ORs) and 95% confidence intervals (CI), with statistical significance set at p <  0.05.

RESULTS

Among 367 participants who delivered at a mean of 38.0 ± 2.2 gestational weeks, the overall PTB rate was 10.1%. After adjusting for potential confounders, we identified the following independent risk factors for PTB: anemia (hemoglobin < 11 g/dl) (OR: 4.27; 95%CI: 1.85-9.85), urinary tract infection (UTI) (OR:9.82; 95%CI: 3.88-24.83), chlamydia infection (OR: 2.79; 95%CI: 1.17-6.63), inadequate minimum dietary diversity for women (MDD-W) score (OR:3.94; CI: 1.57-9.91) and low mid-upper arm circumference (MUAC) < 23 cm (OR: 3.12, 95%CI; 1.31-7.43). indicators of nutritional inadequacy (low MDD-W and MUAC) predicted risk for low birth weight (LBW) but only UTI was associated with LBW in contrast with PTB.

CONCLUSION

Targeted interventions are needed to improve the nutritional status of pregnant women, such as maternal education on dietary diversity and prevention of anemia pre-pregnancy. Additionally, prevention and treatment of maternal infections, especially sexually transmitted infections and UTIs should be reinforced during standard antenatal care screening which currently only includes HIV and syphilis testing.

Prepregnancy Obesity Is Not Associated with Iron Utilization during the Third Trimester

BACKGROUND

An adequate maternal iron supply is crucial for maternal red blood cell (RBC) expansion, placental and fetal growth, and fetal brain development. Obese women may be at risk for poor iron status in pregnancy due to proinflammatory-driven overexpression of hepcidin leading to decreased iron bioavailability.

OBJECTIVE

The objective of this study was to determine the impact of prepregnancy (PP) obesity on third-trimester maternal iron utilization.

DESIGN

Using the stable isotope 57Fe, we measured iron utilization in the third trimester in PP obese [BMI (in kg/m2): ≥30] and nonobese (BMI: 18.5-29.9) women. We also assessed iron status, hepcidin, inflammation, erythropoietin, dietary iron intake, and gestational weight gain. Descriptive and inferential statistical tests (e.g., Student t test, Pearson correlation) were used for data analysis.

RESULTS

Fifty pregnant women (21 PP obese, 29 PP nonobese) were included. Mean age was 27.6 ± 6.8 y and mean gestational age at time of 57Fe administration was 32.7 ± 0.7 wk. Anemia (hemoglobin <11 g/dL for non-black and <10.2 g/dL for black women) affected 38% of women (43% PP obese compared with 35% PP nonobese; P = 0.55). Women with PP obesity had significantly higher C-reactive protein (8.5 compared with 3.4 mg/L, P = 0.0007) and total body iron corrected for inflammation (6.0 compared with 4.3 mg/kg, P = 0.04) compared with the nonobese women. There was no difference in serum hepcidin or iron utilization between the PP BMI groups.

CONCLUSION

This is the first study to assess the impact of PP obesity on maternal iron utilization. We found no difference in iron utilization in the third trimester of pregnancy in women with and without PP obesity. Despite higher frequency of anemia, women with PP obesity had less depleted body iron stores, suggesting some degree of iron sequestration. This finding should be followed up and extended to understand effects on fetal iron bioavailability.

Gestational weight gain and its effect on birth outcomes in sub-Saharan Africa: Systematic review and meta-analysis

INTRODUCTION

An increased metabolic demand during pregnancy is fulfilled by gaining sufficient gestational weight. Women who gain inadequate-weight are at a high-risk of premature birth or having a baby with low-birth weight. However, women who gain excessive-weight are at a high-risk of having a baby with macrosomia. The aim of this review was to determine the distribution of gestational weight gain and its association with birth-outcomes in Sub-Saharan Africa.

METHODS

For this systematic review and meta-analysis, we performed a literature search using PubMed, Medline, Embase, Scopus, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases. We searched grey-literature from Google and Google Scholar, and region-specific journals from the African Journals Online (AJOL) database. We critically appraised the included studies using the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies. Two independent reviewers evaluated the quality of the studies and extracted the data. We calculated pooled relative-risks (RR) with 95% confidence intervals.

RESULTS

Of 1450 retrieved studies, 26 met the inclusion criteria. Sixteen studies classified gestational weight gain according to the United States Institute of Medicine recommendations. The percentage adequate amount of gestational weight ranged from 3% to 62%. The percentage of inadequate weight was >50% among nine studies. Among underweight women, the percentage of women who gained inadequate gestational weight ranged from 67% to 98%. Only two studies were included in the meta-analyses to evaluate the association of gestational weight gain with pre-eclampsia and macrosomia. No difference was observed among women who gained inadequate and adequate gestational weight regarding experiencing pre-eclampsia (RR, 0.71; 95% CI: 0.22, 2.28, P = 0.57). Excessive gestational weight gain was not significantly associated with macrosomia compared to adequate weight gain (RR, 0.68; 95% CI: 0.38, 1.22, P = 0.20).

CONCLUSION

A substantial proportion of sub-Saharan African women gain inadequate gestational weight particularly high among underweight women. Future interventions would need to design effective pre-pregnancy weight management strategies.

Prepregnancy Overweight and Obesity Are Associated with an Increased Risk of Preterm Birth in Chinese Women

INTRODUCTION

The association between obesity before pregnancy and preterm birth varies with age and ethnicity.

OBJECTIVE

To study the association between early body mass index (BMI) and risk of preterm birth in Chinese women.

METHODS

This was a hospital-based retrospective cohort study including 36,596 Chinese women who gave birth to a live singleton infant from 2015 to 2018. Women were classified as underweight (BMI <18.5), normal weight (BMI 18.5 to <23), overweight (BMI 23 to <27.5), or obese (BMI ≥27.5) according to the most recent criteria for Asian women. Multivariate log-binomial regression models were used to estimate the relative risks (RRs) and 95% confidence intervals (95% CIs) for preterm birth among different groups.

RESULTS

Compared to women with normal weight, women with overweight or obesity before pregnancy had an increased risk of preterm birth; the RRs and 95% CIs were 1.22 (95% CI: 1.08-1.37) and 1.30 (95% CI: 1.01-1.69), respectively. The greatest risk of extremely preterm birth was observed in obese women. The estimators were robust when considering the maternal age and rate of gestational weight gain (GWG) during pregnancy.

CONCLUSIONS

Women with overweight and obesity had an increased risk of preterm birth regardless of GWG in early pregnancy. Our study suggests that it is beneficial to lose weight before conception for both overweight and obese women who plan to become pregnant.

Associations between pre-pregnancy body mass index and gestational weight gain with pregnancy outcomes in women with polycystic ovary syndrome

BACKGROUND

The influence of pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) on perinatal outcomes of women with polycystic ovary syndrome (PCOS) remains unclear. Therefore, we explored how the above indicators influence pregnancy outcomes in women with PCOS.

METHODS

A retrospective study was conducted involving the baseline characteristics, laboratory data, and pregnancy outcomes of 722 pregnant women with PCOS. Subjects were grouped in a way to find out risks in their pregnancy outcomes. Multivariable logistic regression analysis was performed to investigate how BMI and GWG were associated with perinatal outcomes.

RESULTS

Among women with PCOS, underweight increased the risk of small for gestational age (SGA) (OR 12.35, 95% CI 3.56-42.82), but reduced the risk of large for gestational age (LGA). Overweight but not obese women were more susceptible to developing preeclampsia (PE) than women with normal weight. In PCOS women with BMI < 25 kg/m² before pregnancy, inadequate GWG was a protective factor for gestational hypertension (GH) and postpartum hemorrhage (PPH), excessive GWG exhibited a positive correlation with LGA. But in PCOS women with BMI ≥ 25 kg/m², excessive GWG increased the probability of undergoing a cesarean section. Inadequate GWG did not reduce the likelihood of LGA in women with BMI ≥ 25 kg/m², and excessive GWG did not reduce the probability of SGA in women with BMI < 25 kg/m².

CONCLUSION

The impacts of pre-pregnancy BMI, GWG on maternal and infant outcomes among PCOS women are similar to reported results in general pregnant women. However, some unique trends were also observed in PCOS women. While the underweight factor significantly increased the risk of SGA birth, overweight but not obesity was correlated with the risk of PE. Inadequate GWG was a protective factor for GH and PPH only in women with pregestational BMI < 25 kg/m². Inadequate GWG did not reduce the probability of LGA in women with BMI ≥ 25 kg/m², and similarly, excessive GWG did not reduce the probability of SGA in women with BMI < 25 kg/m². Overall, these findings indicate that women with PCOS should begin weight management before pregnancy.

Association of prepregnancy body mass index, rate of gestational weight gain with pregnancy outcomes in Chinese urban women

Background

The prevalence of obesity and excessive gestational weight gain (GWG) has been increasing worldwide. The aims of this study were to evaluate associations of prepregnancy body mass index (BMI) and rate of GWG in the 2nd and 3rd trimesters with pregnancy outcomes in Chinese urban women, and to examine the dose-response relationship between rate of GWG and pregnancy outcomes.

Methods

A retrospective analysis included 8926 women who delivered live singletons at ≥28 weeks of gestation between June 2012 and March 2013 among Chinese urban women. BMI was classified into underweight (BMI < 18.5 kg/m²), normal weight (18.5 kg/m² ≤ BMI < 24 kg/m²), overweight (24 kg/m² ≤ BMI < 28 kg/m²) and obese (BMI ≥ 28 kg/m²) according to the Chinese standard. Rate of GWG in the 2nd and 3rd trimesters was classified as insufficient, adequate and excessive if it was below, within, or above the 2009 IOM guidelines (0.44–0.58 kg/w [underweight], 0.35–0.50 kg/w [normal], 0.23–0.33 kg/w [overweight], and 0.17–0.27 kg/w [obese]). Logistic regression models and restricted cubic spline analyses were used to assess the association of prepregnancy BMI and rate of GWG with cesarean delivery, preterm birth, small-for-gestational age (SGA) and large-for-gestational age (LGA).

Results

22.6 and 50.0% of women had insufficient and excessive rate of GWG, respectively. After adjustment for potential confounders, prepregnancy underweight was associated with increased risk of SGA (OR = 1.71, 95% CI: 1.40–2.09), while both overweight and obesity were associated with higher risk of cesarean delivery (overweight: OR [95% CI] = 1.80 [1.56–2.08]; obese: 2.34 [1.69–3.24]) and LGA (overweight: 1.75 [1.44–2.13]; obese: 2.48 [1.71–3.60]). Both insufficient (OR = 1.34, 95% CI: 1.08–1.65) and excessive rates of GWG (OR = 1.44, 95% CI: 1.20–1.73) were associated with higher risk of preterm birth. Insufficient rate of GWG was associated with increased odds of SGA (OR = 1.49, 95% CI: 1.16–1.82), while excessive rate of GWG was associated with higher risk for cesarean delivery (OR = 1.22, 95% CI: 1.10–1.35) and LGA (OR = 1.58, 95% CI: 1.33–1.87). Additionally, there were significant nonlinear associations between rate of GWG and preterm birth (U-shaped, P for nonlinear < 0.001).

Conclusions

Prepregnancy overweight, obesity and underweight, and insufficient and excessive rate of GWG were associated with increased risk of pregnancy outcomes in Chinese urban women.

Electronic supplementary material

The online version of this article (10.1186/s12986-019-0386-z) contains supplementary material, which is available to authorized users.

Rate of gestational weight gain and adverse pregnancy outcomes in rural nulliparous women: a prospective cohort analysis from China

Both inadequate and excessive gestational weight gain (GWG) have been shown to increase the risk of adverse pregnancy outcomes, but the risk profiles of GWG rate are unclear. We aimed to examine the associations between GWG rate in the second/third trimester and a spectrum of pregnancy outcomes. This study consisted of 14 219 Chinese rural nulliparous women who participated in a randomised controlled trial of prenatal micronutrient supplementation during 2006–2009. The outcomes included stillbirth, neonatal and infant death, preterm birth, macrosomia, low birth weight (LBW) and large and small for gestational age (LGA and SGA, respectively). GWG rate was divided into quintiles within each BMI category. Compared with women in the middle quintile, those in the lowest quintile had higher risks of neonatal death (adjusted OR 2·27; 95 % CI 1·03, 5·02), infant death (adjusted OR 1·85; 95 % CI 1·02, 3·37) and early preterm birth (adjusted OR 2·33; 95 % CI 1·13, 4·77), while those in the highest quintile had higher risks of overall preterm birth (adjusted OR 1·28; 95 % CI 1·04, 1·59), late preterm birth (adjusted OR 1·25; 95 % CI 1·00, 1·56), LBW (adjusted OR 1·48; 95 % CI 1·02, 2·15), macrosomia (adjusted OR 1·89; 95 % CI 1·46, 2·45) and LGA (adjusted OR 1·56; 95 % CI 1·31, 1·85). In conclusion, very low and very high GWG rates in the second/third trimester appear to be associated with adverse pregnancy outcomes in Chinese nulliparous women, indicating that an appropriate GWG rate during pregnancy is necessary for neonatal health.

Gestational weight management and pregnancy outcomes among women of advanced maternal age

In this study, we assessed the effects of pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) on the pregnancy outcomes of women of advanced age using a back-propagation (BP) artificial neural network. We conducted a retrospective analysis on postpartum and hospital delivery data from 1,015 women of advanced maternal age (AMA) hospitalized at the Fujian Provincial Maternity and Children's Hospital from January to June, 2017. Pre-pregnancy overweight was found to increase the incidence of gestational diabetes mellitus (GDM), hypertensive disorders complicating pregnancy (HDCP) and fetal macrosomia. In addition, poor weight gain during pregnancy increased the chances of pre-term births (PTBs). Furthermore, excessive weight gain during pregnancy increased the incidence of macrosomia in women of AMA. On the whole, the findings of this study suggest that controlling the pre-pregnancy BMI and the GWG may reduce the incidence of adverse pregnancy outcomes in women of AMA. The BP neural network is suitable for the study of weight changes in this population.

The Association Between Trimester-Specific Weight Gain and Severe Preeclampsia/Adverse Perinatal Outcome in Gestational Diabetes Mellitus Complicated by Preeclampsia: A Retrospective Case Study

INTRODUCTION

Gestational diabetes mellitus (GDM) and preeclampsia share many risk factors, e.g., gestational weight gain (GWG). Previous studies on the co-occurrence of these two diseases cannot powerfully clear up the effects of GWG on perinatal outcome.

METHODS

A total of 329 pregnant women with GDM complicated by preeclampsia were enrolled. Clinical data of mothers and newborns were retrospectively analyzed, including baseline characteristics of pregnant women and pregnancy outcomes. We focused on the association between trimester-specific weight gain and severe preeclampsia (s-PE)/adverse perinatal outcomes in GDM complicated by preeclampsia, including cesarean section (C-sect), preterm birth, and large for gestational age birth (LGA). Regression analysis was used to adjust the impact of confounding factors, including height, age, parity, scarred uterus, and so on.

RESULT

By unconditional regression analysis, middle trimester excessive GWG is a risk factor for LGA [OR 6.586, 95% CI (2.254-19.242), AOR 6.481, 95% CI (2.213-18.981)]; late excessive GWG is a risk factor for s-PE and C-sect [OR 1.683, 95% CI (1.084-2.614), AOR 1.888, 95% CI (1.193-2.990); and OR 1.754, 95% CI (1.121-2.744), AOR 1.841, 95% CI (1.153-2.937)], excessive total GWG is a risk factor for LGA, and is a protective factor for the preterm [OR 5.920, 95% CI (2.479-14.139), AOR 5.602, 95% CI (2.337-13.431); and OR 0.448, 95% CI (0.248-0.841), AOR 0.429, 95% CI (0.235-0.783)].

CONCLUSIONS

The trimester-specific weight gain has a significant impact on the perinatal outcomes among pregnant women with both GDM and preeclampsia. This study is helpful for carry out risk monitoring in time, identifying early warning signs, and improving maternal and infant health.

Maternal body mass index and risk of neonatal adverse outcomes in China: a systematic review and meta-analysis

BACKGROUND

Maternal body mass index is linked to short- and long-term unfavorable health outcomes both for child and mother. We conducted a systematic review and meta-analysis of population-based cohort studies to evaluate maternal BMI and the risk of harmful neonatal outcomes in China.

METHODS

Six databases identified 2454 articles; 46 met the inclusion criteria for this study. The dichotomous data on maternal BMI and harmful neonatal outcomes were extracted. Pooled statistics (odds ratios, ORs) were derived from Stata/SE, ver. 12.0. Sensitivity analyses assessed the robustness of the results. Meta-regression and subgroup meta-analyses explored heterogeneity.

RESULTS

The meta-analysis revealed that compared with normal BMI, high maternal BMI is associated with fetal overgrowth, defined as macrosomia ≥4000 g (OR 1.91, 95% CI 1.75-2.09); birth weight ≥ 90% for gestational age (OR 1.88, 95% CI 1.64-2.15); and increased risk of premature birth (OR 1.38, 95% CI 1.25-2.52) and neonatal asphyxia (OR 1.74, 95% CI 1.39-2.17). Maternal underweight increased the risk of low birth weight (OR 1.61, 95% CI 1.33-1.93) and small for gestational age (OR 1.75, 95% CI 1.51-2.02).

CONCLUSIONS

Raised as well as low pre-pregnancy BMI is associated with adverse neonatal outcomes. Management of weight during pregnancy might help reduce their adverse neonatal outcomes in future intervention studies or programmes.

Gestational diabetes: weight gain during pregnancy and its relationship to pregnancy outcomes

BACKGROUND

Weight gain during pregnancy reflects the mother's nutritional status. However, it may be affected by nutritional therapy and exercise interventions used to control blood sugar in gestational diabetes mellitus (GDM). This study aimed to evaluate weight gain during gestation and pregnancy outcomes among women with GDM.

METHODS

A retrospective study involving 1523 women with GDM was conducted between July 2013 and July 2016. Demographic data, gestational weight gain (GWG), blood glucose, glycated-hemoglobin level, and maternal and fetal outcomes were extracted from medical records. Relationships between GWG and pregnancy outcomes were investigated using multivariate logistic regression.

RESULTS

In total, 451 (29.6%) women showed insufficient GWG and 484 (31.8%) showed excessive GWG. Excessive GWG was independently associated with macrosomia (adjusted odds ratio [aOR] 2.20, 95% confidence interval [CI] 1.50-3.52, P < 0.001), large for gestational age (aOR 2.06, 95% CI 1.44-2.93, P < 0.001), small for gestational age (aOR 0.49, 95% CI 0.25-0.97, P = 0.040), neonatal hypoglycemia (aOR 3.80, 95% CI 1.20-12.00, P = 0.023), preterm birth (aOR 0.45, 95% CI 0.21-0.96, P = 0.040), and cesarean delivery (aOR 1.45, 95% CI 1.13-1.87, P = 0.004). Insufficient GWG increased the incidence of preterm birth (aOR 3.53, 95% CI 1.96-6.37, P < 0.001).

CONCLUSIONS

Both excessive and insufficient weight gain require attention in women with GDM. Nutritional therapy and exercise interventions to control blood glucose should also be used to control reasonable weight gain during pregnancy to decrease adverse pregnancy outcomes.

Blood pressure in early and mid-pregnancy and the risk of small-for-gestational-age birth: findings of a large cohort study in China

The influences of blood pressure in early to mid-pregnancy on the risk of small-for-gestational-age (SGA) birth are not clear. Our objective was to examine the associations of the blood pressure levels at 10 and 18 gestational weeks with the risk of SGA birth. Data were obtained from the Chinese Maternal and Newborn's Health Monitoring System (MNHMS). In total, 50745 Chinese women who delivered a single live infant at a gestational age of between 28 and 42 weeks were included in this analysis. Blood pressure, birth outcome and other related information were obtained during antenatal visits by obstetricians. Logistic regression models were used to examine the associations, adjusting for potential confounders. The total incidence of SGA birth was 8.9%. High blood pressure levels at 10 gestational weeks significantly increased the risk of SGA birth (SBP: RR = 1.32, 95% CI: 1.11-1.56; DBP: RR = 1.10, 95% CI: 1.05-1.14). The incidence of SGA birth was not associated with the DBP at 18 gestational weeks but showed a U-shaped relationship with SBP. A decrease in blood pressure from 10 to 18 gestational weeks was associated with an increased risk of SGA birth (SBP: RR = 1.03, 95% CI: 1.00-1.07; DBP: RR = 1.05, 95% CI: 1.02-1.09). Our results provide evidence on the relationship of blood pressure in early and mid-pregnancy with SGA birth. Higher blood pressures during early pregnancy and greater decreases in blood pressure from early to mid-pregnancy increased the risk of SGA birth, indicating a continuum of risk for SGA birth based on blood pressure starting during early pregnancy.

Gestational weight gain across continents and ethnicity: systematic review and meta-analysis of maternal and infant outcomes in more than one million women

BACKGROUND

The association between Institute of Medicine (IOM) guidelines and pregnancy outcomes across ethnicities is uncertain. We evaluated the associations of gestational weight gain (GWG) outside 2009 IOM guidelines, with maternal and infant outcomes across the USA, western Europe and east Asia, with subgroup analyses in Asia. The aim was to explore ethnic differences in maternal prepregnancy body mass index (BMI), GWG and health outcomes across these regions.

METHODS

Systematic review, meta-analysis and meta-regression of observational studies were used for the study. MEDLINE, MEDLINE In-Process, Embase and all Evidence-Based Medicine (EBM) Reviews were searched from 1999 to 2017. Studies were stratified by prepregnancy BMI category and total pregnancy GWG. Odds ratio (ORs) 95% confidence intervals (CI) applied recommended GWG within each BMI category as the reference. Primary outcomes were small for gestational age (SGA), preterm birth and large for gestational age (LGA). Secondary outcomes were macrosomia, caesarean section and gestational diabetes.

RESULTS

Overall, 5874 studies were identified and 23 were included (n = 1,309,136). Prepregnancy overweight/obesity in the USA, Europe and Asia was measured at 42%, 30% and 10% respectively, with underweight 5%, 3% and 17%. GWG below guidelines in the USA, Europe and Asia was 21%, 18% and 31%, and above was 51%, 51% and 37% respectively. Applying regional BMI categories in Asia showed GWG above guidelines (51%) was similar to that in the USA and Europe. GWG below guidelines was associated with a higher risk of SGA (USA/Europe [OR 1.51; CI 1.39, 1.63]; Asia [1.63; 1.45, 1.82]) and preterm birth (USA/Europe [1.35; 1.17, 1.56]; Asia [1.06; 0.78, 1.44]) than GWG within guidelines. GWG above guidelines was associated with a higher risk of LGA (USA/Europe [1.93; 1.81, 2.06]; Asia [1.68; 1.51 , 1.87]), macrosomia (USA/Europe [1.87; 1.70, 2.06]; Asia [2.18; 1.91, 2.49]) and caesarean (USA/Europe [1.26; 1.21, 1.33]; Asia [1.37; 1.30, 1.45]). Risks remained elevated when regional BMI categories were applied for GWG recommendations. More women in Asia were categorised as having GWG below guidelines using World Health Organization (WHO) (60%) compared to regional BMI categories (16%), yet WHO BMI was not accompanied by increased risks of adverse outcomes.

CONCLUSIONS

Women in the USA and western Europe have higher prepregnancy BMI and higher rates of GWG above guidelines than women in east Asia. However, when using regional BMI categories in east Asia, rates of GWG above guidelines are similar across the three continents. GWG outside guidelines is associated with adverse outcomes across all regions. If regional BMI categories are used in east Asia, IOM guidelines are applicable in the USA, western Europe and east Asia.