Mediators of the association between maternal body mass index and breastfeeding duration in 3 international cohorts

Weight management during pregnancy, what is new?

PURPOSE OF REVIEW

The prevalence of women entering pregnancy with overweight or obesity is increasing which raises concerns for adverse outcomes for mothers and their infants. Evidence suggests that appropriate gestational weight gain is important, irrespective of maternal BMI. The aim of this present article is to review the evidence on weight management during pregnancy and evaluate the evidence on current interventions.

RECENT FINDINGS

There is currently no standardized definition of 'excessive' gestational weight gain or a unified approach to manage gestational weight, despite the rising prevalence of maternal overweight and obesity globally. Recently, the Dietary Intervention in Gestational Diabetes (DiGest) trial showed promising results for energy restriction as a potential strategy to reduce gestational weight gain and improve maternal and infant outcomes. Pharmacological treatments, including GLP-1 receptor agonists, also show promise, but safety concerns remain requiring further research. More studies are needed to assess the effectiveness of both lifestyle and pharmacological interventions to guide future clinical recommendations.

SUMMARY

There is a need for individualized guidelines that consider maternal characteristics including ethnicity, preexisting conditions and emerging health risks, to tackle weight management during pregnancy and improve pregnancy outcomes. Further research is needed on optimal weight management strategies during pregnancy.

Sexual and reproductive health in overweight and obesity: Aims and visions for integrated research approaches

Overweight and obesity increasingly affect women in their reproductive phase, during family planning, pregnancy, breastfeeding and the postpartum period. Overweight and obesity are associated with impaired sexual and reproductive health, including increased rates of infertility, pregnancy complications, and reduced breastfeeding rates. Furthermore, maternal overweight and obesity are associated with long-term negative health consequences for the child, such as an increased risk for respiratory and metabolic disease. With the Junior Research Center for Reproduction: Sexual and Reproductive Health in Overweight and Obesity (SRHOO Center), we aim to address the effects of overweight and obesity on sexual and reproductive health in an interdisciplinary approach, combining the areas of obstetrics and midwifery, sexual health research, basic research in feto-maternal medicine and glycoimmunology, pediatrics, as well as endocrinology, metabolism and bariatric surgery. Combining these areas of expertise, we seek (1) to understand the effects of overweight and obesity on sexual and reproductive health in different patient groups, focusing on their specific needs in order to provide appropriate counselling and access to healthcare; (2) to improve reproductive health in different groups of overweight and obese patients; and (3) to create interdisciplinary, comprehensive scientific and clinical training regarding sexual and reproductive health in overweight and obese patients. In this short introduction to the SRHOO Center, we provide information on its structure, aims and individual projects as well as its presumed long-term implications for clinical care and public health.

Breastfeeding initiation according to the severity of Class 3 obesity

Background: Class 3 obesity is composed of morbid (BMI 40-49 kg/m2) and extreme (BMI ≥ 50 kg/m2) subgroups. Adverse perinatal outcomes have been associated with obesity; however, data on breastfeeding (BF) initiation for women in either group remains limited.Objective: To compare BF initiation rates (exclusive or partial BF) and related comorbidities of 890 women with morbid and 890 with extreme obesity matched by race, parity, and year of delivery.Methods: Retrospective cohort study of women who delivered singletons at ≥ 34 weeks gestation (2013-2021). Those who had bariatric surgery or infants with major malformations were excluded.Results: Both groups were similar in: primiparity (38%), age (29y), white race (58%), African American (36%), current (10 vs 12%) and former (25 vs 27%) smokers, gestational hypertension (15 vs 16%), polycystic ovary syndrome (5 vs 7%), gastroesophageal reflux disease (10 vs 10%), and anemia (17 vs 17%). Women in the extreme group had a higher prevalence of gestational (17 vs 12%) and pregestational diabetes (12 vs 6%), chronic hypertension (41 vs 17%), severe preeclampsia (18 vs 12%), obstructive sleep apnea (12 vs 3%), asthma (22 vs 16%), and cesarean deliveries (62 vs 44%). Intention to BF (64 vs 71%), exclusive BF (23 vs 34%), and BF initiation (57 vs 64%) rates were lower in the extreme obesity group at discharge.Conclusion: Higher frequency of comorbidities in the extreme obesity group highlights the need for antenatal, intrapartum, and postpartum targeted interventions if the benefits of BF to mothers and infants are to be realized.

Impact of Maternal Body Composition, Hydration, and Metabolic Health on Breastfeeding Success: A Comprehensive Review

It is well established that breastfeeding provides significant health benefits for both the mother and the infant. The World Health Organization recommends initiating breastfeeding within the first hour after birth and continuing exclusive breastfeeding for 6 months. Successful breastfeeding is influenced not only by the proper physiological preparation of the body and the action of pregnancy-related hormones but also by the mother's overall health status. However, the role of maternal body composition and metabolic condition in breastfeeding success has received little attention. To better understand the impact of these factors on breastfeeding effectiveness, we reviewed the latest research on this topic, with particular emphasis on the role of hydration and lipid metabolism. Our narrative review indicates that the amount and distribution of water and adipose tissue are crucial for successful lactation and that various hormonal imbalances and metabolic disorders increase the risk of delayed breastfeeding initiation, shortened breastfeeding duration, or insufficient milk production. In light of our findings, measurement methods for assessing described parameters were also introduced. This article aims to review the effects of maternal body composition, hydration status, and metabolic and social factors on lactation and breastfeeding.

Association of breastfeeding duration with overweight and obesity among women in Ghana

Background

There is a general concurrence on the health benefits that breastfeeding confers to children, including offering maximal protection against obesity across their life course. However, the scientific evidence on similar benefits for women who breastfeed their children remains inconclusive. This study contributes to the discourse by examining the association of breastfeeding duration with overweight and obesity among women in Ghana.

Methods

Data on 8,516 women of reproductive age were pooled from the last five (5) Ghana Demographic and Health Surveys, and analysed using descriptive proportions and logistic regression models.

Results

The prevalence of overweight and obesity was about 8% lower for women who breastfed their children beyond 18 months (overweight = 13%, obesity = 5%) compared with women who did not breastfeed (overweight = 21%, obesity = 13%) their children at all. With reference to women who did not breastfeed their children, a significant lower odds of obesity was observed for those who breastfed their children for 13-18 months (OR = 0.46, 95% CI = 0.268, 0.864) and >18 months (OR = 0.41, 95% CI = 0.216, 0.764), after adjusting for possible confounding factors.

Discussion

Women who breastfeed their children for a minimum of 12 months have lower risk of developing obesity. Promoting prolonged breastfeeding among mothers could be an effective pathway to preventing obesity among women in Ghana.

Negative association between higher maternal pre-pregnancy body mass index and breastfeeding outcomes is not mediated by DNA methylation

The benefits of breastfeeding for the health and wellbeing of both infants and mothers are well documented, yet global breastfeeding rates are low. One factor associated with low breast feeding is maternal body mass index (BMI), which is used as a measure of obesity. The negative relationship between maternal obesity and breastfeeding is likely caused by a variety of social, psychological, and physiological factors. Maternal obesity may also have a direct biological association with breastfeeding through changes in maternal DNA methylation. Here, we investigate this potential biological association using data from a UK-based cohort study, the Avon Longitudinal Study of Parents and Children (ALSPAC). We find that pre-pregnancy body mass index (BMI) is associated with lower initiation to breastfeed and shorter breastfeeding duration. We conduct epigenome-wide association studies (EWAS) of pre-pregnancy BMI and breastfeeding outcomes, and run candidate-gene analysis of methylation sites associated with BMI identified via previous meta-EWAS. We find that DNA methylation at cg11453712, annotated to PHTP1, is associated with pre-pregnancy BMI. From our results, neither this association nor those at candidate-gene sites are likely to mediate the link between pre-pregnancy BMI and breastfeeding.

Is Maternal Body Weight or Composition Associated with Onset of Lactogenesis II, Human Milk Production, or Infant Consumption of Mother's Own Milk? A Systematic Review and Meta-Analysis

Maternal adiposity impacts lactation performance, but the pathways are unclear. We conducted a systematic review to understand whether maternal adiposity (body mass index [BMI] or percentage fat mass) is associated with onset of lactogenesis II (copious milk; hours), human milk production (expressed volume/24 h), and infant consumption of mother's own milk (volume/24 h). We used random-effects standard meta-analyses to compare the relative risk (RR) of delayed lactogenesis II (>72 h) between mothers classified as underweight (BMI <18.5 kg/m2), healthy weight (BMI, 18.5-24.9 kg/m2), and overweight/obese (BMI ≥25 kg/m2) and random-effects meta-regressions to examine associations with hours to lactogenesis II and infant milk consumption. The certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation approach. We included 122 articles. Mothers with underweight (RR: 0.64; 95% CI: 0.49, 0.83; I2 = 39.48%; 8 articles/data points) or healthy weight status (RR: 0.67; 95% CI: 0.57, 0.79; I2 = 70.91%; 15 articles/data points) were less likely to experience delayed lactogenesis II than mothers with overweight/obesity. We found no association between maternal BMI and time to onset of lactogenesis II (β: 1.45 h; 95% CI: -3.19, 6.09 h; P = 0.52, I2 = 0.00%; 8 articles, 17 data points). Due to limited data, we narratively reviewed articles examining BMI or percentage fat mass and milk production (n = 6); half reported an inverse association and half no association. We found no association between maternal BMI (β: 6.23 mL; 95% CI: -11.26, 23.72 mL; P = 0.48, I2 = 47.23%; 58 articles, 75 data points) or percentage fat mass (β: 7.82 mL; 95% CI: -1.66, 17.29 mL; P = 0.10, I2 = 28.55%; 30 articles, 41 data points) and infant milk consumption. The certainty of evidence for all outcomes was very low. In conclusion, mothers with overweight/obesity may be at risk of delayed lactogenesis II. The available data do not support an association with infant milk consumption, but the included studies do not adequately represent mothers with obesity. This study was registered in PROSPERO as 285344.

Human Milk Composition Is Associated with Maternal Body Mass Index in a Cross-Sectional, Untargeted Metabolomics Analysis of Human Milk from Guatemalan Mothers

Background

Maternal overweight and obesity has been associated with poor lactation performance including delayed lactogenesis and reduced duration. However, the effect on human milk composition is less well understood.

Objectives

We evaluated the relationship of maternal BMI on the human milk metabolome among Guatemalan mothers.

Methods

We used data from 75 Guatemalan mothers who participated in the Household Air Pollution Intervention Network trial. Maternal BMI was measured between 9 and <20 weeks of gestation. Milk samples were collected at a single time point using aseptic collection from one breast at 6 mo postpartum and analyzed using high-resolution mass spectrometry. A cross-sectional untargeted high-resolution metabolomics analysis was performed by coupling hydrophilic interaction liquid chromatography (HILIC) and reverse phase C18 chromatography with mass spectrometry. Metabolic features associated with maternal BMI were determined by a metabolome-wide association study (MWAS), adjusting for baseline maternal age, education, and dietary diversity, and perturbations in metabolic pathways were identified by pathway enrichment analysis.

Results

The mean age of participants at baseline was 23.62 ± 3.81 y, and mean BMI was 24.27 ± 4.22 kg/m2. Of the total metabolic features detected by HILIC column (19,199 features) and by C18 column (11,594 features), BMI was associated with 1026 HILIC and 500 C18 features. Enriched pathways represented amino acid metabolism, galactose metabolism, and xenobiotic metabolic metabolism. However, no significant features were identified after adjusting for multiple comparisons using the Benjamini-Hochberg false discovery rate procedure (FDRBH < 0.2).

Conclusions

Findings from this untargeted MWAS indicate that maternal BMI is associated with metabolic perturbations of galactose metabolism, xenobiotic metabolism, and xenobiotic metabolism by cytochrome p450 and biosynthesis of amino acid pathways. Significant metabolic pathway alterations detected in human milk were associated with energy metabolism-related pathways including carbohydrate and amino acid metabolism.This trial was registered at clinicaltrials.gov as NCT02944682.

Anthropometric Changes During Pregnancy and Their Association with Adequacy of Gestational Weight Gain

Background

Gestational weight gain (GWG) is an expected component of a healthy pregnancy. Gaining weight within the recommended range helps support the mother's health by providing energy reserves and nutrients to meet the increased metabolic demands during pregnancy. Too much or too little GWG has been associated with adverse health outcomes for the mother and child.

Objective

The objective of the study was to examine how changes in anthropometric indicators during pregnancy, including fat gain, vary, compare changes among body mass index (BMI) (kg/m2) groups, and examine how the changes were associated with adequacy of GWG defined using the 2009 Institute of Medicine guidelines.

Methods

Data came from a cohort of 360 pregnant women with measured anthropometric indicators (weight, midupper arm circumference, and skin folds of the triceps, thigh, and upper iliac) at <12-, 16 to 22-, and 28 to 32-wks of gestation. Fat gain was calculated using a formula. Analysis of variance was used to test for differences in anthropometric changes by BMI and adequacy of GWG in the third trimester. Multiple logistic regression was used to examine associations between changes in anthropometric indicators and GWG recommendations.

Results

Women with normal weight had greater increases in all anthropometric indicators, which differed from women with obesity, who had negative changes and gained less weight. Women who gained inadequately (21%) had negative changes that were all less, compared with women who gained adequately (46%) (except in upper iliac) or excessively (34%). Women with BMI of >25 who gained adequately also had negative changes. Logistic regression results indicated that changes in midupper arm circumference, triceps, and thigh skin folds, and fat gain were all inversely associated with inadequate GWG, whereas all indicators were positively associated with excessive GWG.

Conclusions

Anthropometric changes during pregnancy differ by BMI and are associated with adequacy of GWG. Women who gained adequately had minimal fat gain, lending support for current GWG guidelines.