ArticleBMC medicine2024
Rethinking causal assumptions about maternal BMI, gestational weight gain, and adverse pregnancy outcomes.
Article in BMC medicine, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 2 of them syntheses that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
13 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Preconception Interventions in Women at High Risk of Developing Gestational Diabetes: A Systematic Review.Maternal and child health journal · 2026Pooled it
- FIGO good practice recommendations on preconception care: A strategy to prevent preterm birth.International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics · 2025Guideline
- Observational
- Linking maternal BMI trajectories from prepregnancy to postpartum with breast milk fat composition: a retrospective longitudinal study.International breastfeeding journal · 2026Article
- Effects of gestational weight gain based on weight-recommended guidelines (2022) in China on maternal and neonatal outcomes: a retrospective cohort study.BMC public health · 2026Article
- Relationship Between Intraocular Pressure and Carbonic Anhydrase Enzyme Activity in Cattle: Implications for Veterinary Ophthalmology.Veterinary medicine and science · 2026Article
- Article
- Neurodevelopmental Pathways from Maternal Obesity to Offspring Outcomes: An Umbrella Review of Cognitive and Behavioral Consequences Across Development.Healthcare (Basel, Switzerland) · 2025Review
- Vascular Assessment Stratifying Preeclampsia Risk in Overweight/Obese Women.Hypertension (Dallas, Tex. : 1979) · 2025Observational
- Association of maternal body mass index with hemodynamic and vascular alterations at 35-37 weeks' gestation.Ultrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology · 2025Observational
- Socioecological correlates of parental lifestyle patterns during the antenatal period.The international journal of behavioral nutrition and physical activity · 2025Article
- Maternal pre-pregnancy body mass index and gestational weight gain on adverse birth outcomes in Chinese newborns: a retrospective study.Journal of health, population, and nutrition · 2024Article
- Precision Interventions Targeting the Maternal Metabolic Milieu for Healthy Pregnancies in Obesity.Current diabetes reports · 2024Review
Corrections and comments
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Authors and funding
5 authors.
Funding
Abstract
backgroundThe aim of this study was to evaluate commonly assumed causal relationships between body mass index (BMI), gestational weight gain (GWG), and adverse pregnancy outcomes, which have formed the basis of guidelines and interventions aimed at limiting GWG in women with overweight or obesity. We explored relationships between maternal BMI, total GWG (as a continuous variable and as 'excessive' GWG), and pregnancy outcomes (including infant birthweight measures and caesarean birth).
methodsAnalysis of individual participant data (IPD) from the i-WIP (International Weight Management in Pregnancy) Collaboration, from randomised trials of diet and/or physical activity interventions during pregnancy reporting GWG and maternal and neonatal outcomes. Women randomised to the control arm of 20 eligible randomised trials (4370 of 8908 participants) from the i-WIP dataset of 36 randomised trials (total 12,240 women). The main research questions were to characterise the relationship between maternal BMI and (a) total GWG, (b) the risk of 'excessive' GWG (using the Institute of Medicine's guidelines), and (c) adverse pregnancy outcomes as mediated via GWG versus other pathways to determine the extent to which the observed effect of maternal BMI on pregnancy outcomes is mediated via GWG. We utilised generalised linear models and regression-based mediation analyses within an IPD meta-analysis framework.
resultsMean GWG decreased linearly as maternal BMI increased; however, the risk of 'excessive' GWG increased markedly at BMI category thresholds (i.e. between the normal and overweight BMI category threshold and between the overweight and obese BMI category threshold). Increasing maternal BMI was associated with increased risk of all pregnancy outcomes assessed; however, there was no evidence that this effect was mediated via effects on GWG.
conclusionsThere is evidence of a meaningful relationship between maternal BMI and GWG and between maternal BMI and adverse pregnancy outcomes. There is no evidence that the effect of maternal BMI on outcomes is via an effect on GWG. Our analyses also cast doubt on the existence of a relationship between 'excessive' GWG and adverse pregnancy outcomes. Our findings challenge the practice of actively managing GWG throughout pregnancy.
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