Preconception management of women with obesity: A systematic review

Teratogenic risks of treated and untreated maternal obesity

Untreated obesity in pregnancy is associated with adverse fetal and neonatal outcomes that influence the long-term offspring health trajectory, propagating obesity and cardiometabolic disease from one generation to the next. The current efforts to reduce the risk of these negative outcomes through preconception weight loss remain largely ineffective. Anti-obesity medications (AOMs) are an understudied option for this indication, likely due to the potential for teratogenicity with accidental exposure during pregnancy. However, the current recommendation to discontinue all AOMs prior to conception fails to frame obesity within the chronic disease paradigm typically used for preconception counseling. Evolving evidence suggests that glucagon-like peptide 1 receptor agonists (GLP-1 RAs), the newest and most effective AOM class, may be safe in early pregnancy. Although further research is needed, counseling about GLP-1 RAs during pregnancy should include the potential for both risk and benefit. This review summarizes the known risks that obesity in pregnancy poses to the offspring and discusses the benefits and limitations of current treatment strategies. While there remain several barriers to optimal preconception and prenatal care for people with obesity, this review aims to arm providers with the knowledge needed for patient-centered counseling prior to and during pregnancy.

Measuring Dietary Intake of Pregnant Women Post-Bariatric Surgery: Do Women Meet Recommendations?

Background: Bariatric surgery is increasingly offered to women of childbearing age and significantly reduces food intake and nutrient absorption. During pregnancy, associated risks, including micronutrient deficiency, are accentuated. This study describes maternal dietary intake and adherence to dietary recommendations in pregnant women with a history of bariatric surgery. Methods: Women aged 18-45 with singleton pregnancies post-bariatric surgery were recruited at <23 weeks of gestation and followed until birth. Dietary intake was measured using three non-consecutive 24 h recalls at enrolment and at 28 and 36 weeks using the standardized tool ASA24-Australia. Micronutrient supplementation dose and adherence was reported using the Brief Medication Adherence Questionnaire. Mean macronutrient intake was calculated from all diet recalls. Micronutrient intake was determined from diet recalls and from supplementation. Intake was compared to the recommended daily intakes for pregnancy. Results: Sixty-three women participated in the study. The participants met 65 ± 17.3% (mean ± SD) of estimated energy requirements, 53(23)% (median(IQR)) of fiber requirements, and exceeded fat and saturated fat recommendations. Dietary intake levels of iron, folate, zinc, calcium, and vitamin A were below recommended levels. Gastric bypass recipients consumed significantly less folate (p = 0.008), vitamin A (p = 0.035), and vitamin E (p = 0.027) than women post-gastric sleeve or gastric band. Multivitamins were used by 80% (n = 55) of participants at study enrolment, which increased their mean intake of all micronutrients to meet recommendations. Conclusions: Women who conceive post-bariatric surgery may require targeted support to meet the recommended nutrient intake. Micronutrient supplementation enables women to meet nutrient recommendations for pregnancy and is particularly important for gastric bypass recipients.

Effectiveness of preconception weight loss interventions on fertility in women: a systematic review and meta-analysis

IMPORTANCE

Weight loss before conception is recommended for women with overweight or obesity to improve fertility outcomes, but evidence supporting this recommendation is mixed.

OBJECTIVE

To examine the effectiveness of weight loss interventions using lifestyle modification and/or medication in women with overweight or obesity on pregnancy, live birth, and miscarriage.

DATA SOURCES

An electronic search of MEDLINE, Embase, Cochrane Library, including Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials, and Cumulative Index to Nursing and Allied Health Literature was conducted through July 6, 2022, via Wiley.

STUDY SELECTION AND SYNTHESIS

Randomized controlled trials examining weight loss interventions through lifestyle and/or medication in women with overweight or obesity planning pregnancy were included. Random-effects meta-analysis was conducted, reporting the risk ratio (RR) for each outcome. Subgroup analyses were conducted by intervention type, type of control group, fertility treatment, intervention length, and body mass index (BMI).

MAIN OUTCOME(S)

Clinical pregnancy, live birth, and miscarriage events.

RESULT(S)

A narrative review and meta-analysis were possible for 16 studies for pregnancy (n = 3,588), 13 for live birth (n = 3,329), and 11 for miscarriage (n = 3,248). Women randomized and exposed to a weight loss intervention were more likely to become pregnant (RR = 1.24, 95% CI 1.07-1.44; I2 = 59%) but not to have live birth (RR = 1.19, 95% CI 0.97-1.45; I2 = 69%) or miscarriage (RR = 1.17, 95% CI 0.79-1.74; I2 = 31%) compared with women in control groups. Subgroup analyses revealed women randomized to weight loss interventions lasting 12 weeks or fewer (n = 9, RR = 1.43; 95% CI 1.13-1.83) and women with a BMI ≥ 35 kg/m2 (n = 7, RR = 1.54; 95% CI, 1.18-2.02) were more likely to become pregnant compared with women in the control groups. Miscarriage was higher in intervention groups who underwent fertility treatment (n = 8, RR 1.45; 95% CI 1.07-1.96).

CONCLUSION(S)

Pregnancy rates were higher in women undergoing preconception weight loss interventions with no impact on live birth or miscarriage rates. Findings do not support one-size-fits-all recommendation for weight loss through lifestyle modification and/or medication in women with overweight or obesity immediately before conception to improve live birth or miscarriage outcomes.

Obesity and recurrent miscarriage: The interconnections between adipose tissue and the immune system

Currently, obesity is considered a global public health problem. It is the main risk factor for noncommunicable diseases and reproductive complications, such as recurrent miscarriage (RM). RM affects approximately 1% of couples of reproductive age, and recent studies suggest that its prevalence is increasing. Immunological abnormalities may be responsible for a significant number of cases of unexplained RM. Obesity is recognized as a chronic low-grade inflammatory condition. The accumulation of fat in obese adipose tissue promotes changes in the local and systemic immune response. Adipokines, exosomes, micro-RNAs, lipids, and other factors released or secreted by adipose tissue are responsible for the interconnection between obesity and the immune system. Obesity-induced dysregulation of the innate and acquired immune response is also involved in the immunopathology of pregnancy loss in patients with unexplained RM. Therefore, understanding the communication pathways between maternal adipose tissue and the immune response in women living with obesity and RM is an important objective. Thus, diagnostic tools and new immunomodulatory therapies may be proposed for the management of patients with concurrent obesity and RM.

Using a Very Low Energy Diet to Achieve Substantial Preconception Weight Loss in Women with Obesity: A Review of the Safety and Efficacy

Obesity in women of reproductive age is common. Emerging evidence suggests that maternal obesity not only increases the risk of adverse pregnancy outcomes but also has an enduring impact on the metabolic health of the offspring. Given this, management of obesity prior to pregnancy is critically important. Almost all international guidelines suggest that women with obesity should aim to achieve weight loss prior to pregnancy. However, current pre-conception weight loss therapies are sub-optimal. Lifestyle modification typically results in modest weight loss. This may assist fertility but does not alter pregnancy outcomes. Bariatric surgery results in substantial weight loss, which improves pregnancy outcomes for the mother but may be harmful to the offspring. Alternative approaches to the management of obesity in women planning pregnancy are needed. Very low energy diets (VLEDs) have been proposed as a possible tool to assist women with obesity achieve weight loss prior to conception. While VLEDs can induce substantial and rapid weight loss, there are concerns about the impact of rapid weight loss on maternal nutrition prior to pregnancy and about inadvertent exposure of the early fetus to ketosis. The purpose of this review is to examine the existing literature regarding the safety and efficacy of a preconception VLED program as a tool to achieve substantial weight loss in women with obesity.

Developing a lifestyle intervention program for overweight or obese preconception, pregnant and postpartum women using qualitative methods

The time period before, during and after pregnancy represents a unique opportunity for interventions to cultivate sustained healthy lifestyle behaviors to improve the metabolic health of mothers and their offspring. However, the success of a lifestyle intervention is dependent on uptake and continued compliance. To identify enablers and barriers towards engagement with a lifestyle intervention, thematic analysis of 15 in-depth interviews with overweight or obese women in the preconception, pregnancy or postpartum periods was undertaken, using the integrated-Promoting Action on Research Implementation in Health Services framework as a guide to systematically chart factors influencing adoption of a novel lifestyle intervention. Barrier factors include time constraints, poor baseline knowledge, family culture, food accessibility, and lack of relevant data sources. Enabling factors were motivation to be healthy for themselves and their offspring, family and social support, a holistic delivery platform providing desired information delivered at appropriate times, regular feedback, goal setting, and nudges. From the findings of this study, we propose components of an idealized lifestyle intervention including (i) taking a holistic life-course approach to education, (ii) using mobile health platforms to reduce barriers, provide personalized feedback and promote goal-setting, and (iii) health nudges to cultivate sustained lifestyle habits.

Trends of central obesity and associations with nutrients intake and daily behaviors among women of childbearing age in China

Background

Obesity among women of childbearing age has becoming an important public health concern. We aimed to describe the trends of central obesity among Chinese women of childbearing age from 2004 to 2011 and to examine its associations with nutrients intake and daily behaviors.

Methods

Longitudinal data were derived from the China Health and Nutrition Survey. Participants consisted of 2481 women aged 15–44 years old. WC (Waist circumference) and WHtR (Waist to height ratio) were adopted as indicators of central obesity. Generalized linear mixed model was performed to analyze the associations of nutrients intake and daily behaviors with central obesity.

Results

From 2004 to 2011, the prevalence of central obesity among Chinese women of childbearing age increased from 21.6 to 30.7% (WC as indice) or from 22.8 to 32.6% (WHtR as indice) (both p < 0.001). Protein intake above the AMDR (Acceptable macronutrient distribution range) (OR = 1.21, 95% CI 1.05–1.39, p < 0.01) and non-participation in LTPA (Leisure time physical activity) (OR = 1.45, 95% CI 1.17–1.80, p < 0.001) were risk factors for high WC, and the latter was also associated with high WHtR (OR = 1.36, 95% CI 1.10–1.67, p < 0.01). For those women who had high WC & high WHtR, the impacts of protein intake and LTPA became stronger, especial LTPA (OR = 1.53, 95% CI 1.21–1.94, p < 0.001). Age-stratified analyses found that non-participation in LTPA was key factor for central obesity in 15–34 age group, while protein intake above the AMDR was pronounced in the 35–44 age group.

Conclusions

Non-participation in LTPA and protein intake above the AMDR were significant contributors of central obesity, which could be intervention targets to deal with the growing trend of central obesity among women of childbearing age.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-022-01600-9.

Interconception Care for Primary Care Providers: Consensus Recommendations on Preconception and Postpartum Management of Reproductive-Age Patients With Medical Comorbidities

Severe maternal morbidity and mortality continue to increase in the United States, largely owing to chronic and newly diagnosed medical comorbidities. Interconception care, or care and management of medical conditions between pregnancies, can improve chronic disease control before, during, and after pregnancy. It is a crucial and time-sensitive intervention that can decrease maternal morbidity and mortality and improve overall health. Despite these potential benefits, interconception care has not been well implemented by the primary care community. Furthermore, there is a lack of guidelines for optimizing preconception chronic disease, risk stratifying postpartum chronic diseases, and recommending general collaborative management principles for reproductive-age patients in the period between pregnancies. As a result, many primary care providers, especially those without obstetric training, are unclear about their specific role in interconception care and may be unsure of effective methods for collaborating with obstetric care providers. In particular, internal medicine physicians, the largest group of primary care physicians, may lack sufficient clinical exposure to medical conditions in the obstetric population during their residency training and may feel uncomfortable in caring for these patients in their subsequent practice.

The objective of this article is to review concepts around interconception care, focusing specifically on preconception care for patients with chronic medical conditions (eg, chronic hypertension, chronic diabetes mellitus, chronic kidney disease, venous thromboembolism, and obesity) and postpartum care for those with medically complicated pregnancies (eg, hypertensive disorders of pregnancy, gestational diabetes mellitus, excessive gestational weight gain, peripartum cardiomyopathy, and peripartum mood disorders). We also provide a pragmatic checklist for preconception and postpartum management.

A Pilot Randomized Controlled Trial of a Partial Meal Replacement Preconception Weight Loss Program for Women with Overweight and Obesity

About half of Australian women have a body mass index in the overweight or obese range at the start of pregnancy, with serious consequences including preterm birth, gestational hypertension and diabetes, caesarean section, stillbirth, and childhood obesity. Trials to limit weight gain during pregnancy have had limited success and reducing weight before pregnancy has greater potential to improve outcomes. The PreBabe Pilot study was a randomised controlled pilot trial to assess the feasibility, acceptability and potential weight loss achieved using a commercial online partial meal replacement program, (MR) vs. telephone-based conventional dietary advice, (DA) for pre-conception weight-loss over a 10-week period. Women 18–40 years of age with a BMI ≥ 25 kg/m² planning pregnancy within the next 6 to 12 months were included in the study. All participants had three clinic visits with a dietitian and one obstetric consultation. In total, 50 women were enrolled in the study between June 2018 and October 2019–26 in MR and 24 in DA. Study retention at the end of 10 week intervention 81% in the MR arm and 75% in the DA arm. In the-intention-to-treat analysis, women using meal replacements lost on average 5.4 ± 3.1% body weight compared to 2.3 ± 4.2% for women receiving conventional advice (p = 0.029). Over 80% of women in the MR arm rated the support received as excellent, compared to 39% in the DA arm (p < 0.001). Women assigned to the MR intervention were more likely to achieve pregnancy within 12 months of the 10 week intervention (57% (12 of 21) women assigned to MR intervention vs. 22% (4 of 18) assigned to the DA group (p = 0.049) became pregnant). The findings suggest that a weight loss intervention using meal replacements in the preconception period was acceptable and may result in greater weight loss than conventional dietary advice alone.

Impact of preconception weight loss on fasting glucose and pregnancy outcomes in women with obesity: A randomized trial

OBJECTIVE

This study examined the effectiveness of a nonsurgical, preconception weight loss intervention on pregnancy outcomes in women with obesity.

METHODS

This was a two-arm, parallel-group randomized controlled trial. A total of 164 women with BMI 30 to 55 kg/m² who were aged 18 to 38 years and planning pregnancy were randomized to a 12-week standard dietary intervention (SDI; n = 79) or a modified very low-energy diet (VLED; n = 85). Participants were observed for ≤48 weeks while trying for pregnancy and then during pregnancy. The primary outcome was maternal fasting plasma glucose at 26 to 28 weeks' gestation. Exploratory outcomes were individual and composite obesity-related adverse pregnancy outcomes.

RESULTS

Weight loss was greater in the VLED group (SDI 3.2 [0.6] kg vs. VLED 13.0 [0.5] kg, p < 0.01). In completers who had a singleton live birth (SDI 22/79 vs. VLED 35/85, p = 0.10), there was no difference in fasting glucose at 26 to 28 weeks' gestation (SDI 4.8[0.2] mmol/L vs. VLED 4.6 [0.1] mmol/L, p = 0.42). However, the composite of adverse pregnancy outcomes was significantly lower in the VLED group (p < 0.001).

CONCLUSIONS

Substantial prepregnancy weight loss in women with obesity does not alter fasting glucose at 26 to 28 weeks' gestation but does reduce a composite of adverse pregnancy outcomes. A better understanding of metabolic changes in pregnancy after preconception weight loss may assist in improving maternal and neonatal health outcomes.

Healthy for My Baby Research Protocol- a Randomized Controlled Trial Assessing a Preconception Intervention to Improve the Lifestyle of Overweight Women and Their Partners

Background: Preconception lifestyle interventions appear promising to reduce pregnancy complications, prevent adult cardiometabolic diseases, and prevent childhood obesity. These interventions have almost exclusively been studied in populations of obese infertile women. The development of preconception lifestyle interventions targeting a broader population of overweight and obese women without a history infertility and their partners is needed.

Methods: This study is a multicenter open label parallel group randomized controlled trial. Sixty-eight non-infertile women with overweight or obesity in the preconception period and their partners will be recruited from the Sherbrooke and Quebec City regions. The couples will be randomized in a 1:1 ratio to receive the Healthy for my Baby intervention or standard care in the preconception period and pregnancy. Women and their partners will be invited to take part in this lifestyle intervention which includes motivational interviews and daily self-monitoring of lifestyle goals through a mobile phone application. The primary endpoint of this study is the diet quality of women during the preconception period, which will be evaluated using the C-HEI 2007 score at baseline, 2, 4- and 6-months following study enrolment. Women's dietary quality will also be evaluated through the measure of urinary biomarkers of habitual dietary intake at baseline and 2 months in preconception, and 24–26 weeks in pregnancy. Additional indicators of women's lifestyle as well as anthropometric measures will be documented in preconception and pregnancy. For the pregnancy period, the main secondary endpoint is the pattern of gestational weight gain. Pregnancy and neonatal complications will also be evaluated. For partners, diet quality, other lifestyle habits, and anthropometric measures will be documented in the preconception and pregnancy periods.

Discussion: This study will evaluate the effectiveness of a low-cost intervention designed to improve diet and other lifestyle characteristics of women in the preconception period who are overweight or obese. If the Healthy for my Baby intervention is efficacious regarding dietary measures, larger trials will be needed to evaluate the impact of this intervention on the rates of pregnancy complications, childhood obesity, and adult cardiometabolic disease.

Clinical Trial Registration:clinicaltrials.gov (NCT04242069).

Associations of Pregnancy After Bariatric Surgery with Long-Term Weight Trajectories and Birth Weight: LABS-2 Study

OBJECTIVE

This study aimed to examine whether pregnancy following bariatric surgery affects long-term maternal weight change and offspring birth weight.

METHODS

Using data from the Longitudinal Assessment of Bariatric Surgery (LABS)-2 study, linear regression was used to evaluate percent change in total body weight over a 5-year follow-up period among reproductive-aged women who underwent Roux-en-Y gastric bypass or laparoscopic adjustable gastric banding as well as evaluate the association of bariatric procedure type and offspring birth weight.

RESULTS

Of 727 women with preoperative age of 36.1 (6.3) years (mean [SD]) and BMI of 46.9 (7.0) kg/m² , 80 (11%) reported at least one pregnancy. After adjusting for covariates, percent change in total body weight was not significantly different between women who became pregnant and those who did not during a 5-year follow-up period (β = 2.02; 95% CI: -1.03 to 5.07; P = 0.19). Additionally, mean birth weight was not significantly different between mothers who underwent Roux-en-Y gastric bypass versus laparoscopic adjustable gastric banding (P = 0.99).

CONCLUSIONS

Postoperative pregnancy did not diminish long-term weight loss in women in the LABS-2 study. The finding of comparable weight loss is relevant for providers counseling women of reproductive age on weight-loss expectations and family planning following bariatric surgery.