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

Investigating discrepancies in findings between rigorous randomized trials and meta-analyses evaluating pregnancy interventions to limit gestational weight gain

INTRODUCTION

Robust randomized trials consistently demonstrate little impact from diet and physical activity interventions on gestational weight gain (GWG) and clinical outcomes, although meta-analyses report some benefit. Our aim was to evaluate the effect of trial quality on treatment effect estimates and review conclusions.

METHODS

We conducted a systematic review of dietary and/or physical activity interventions for pregnant women with a body mass index ≥18.5 kg/m2. We assessed studies for risk of bias and methodological features impacting reliability. Outcomes included GWG; gestational diabetes mellitus (GDM); pre-eclampsia; caesarean birth; and birth weight measures. For each outcome, a sequence of meta-analyses was performed based on intervention group and level of potential bias in the effect estimate.

RESULTS

We identified 128 eligible studies. The most robust estimate from a combined diet and physical activity behavioral intervention, with only studies at negligible risk of bias, was a difference in GWG of 1.10 kg (95% CI -1.62 to -0.58; 17,755 women). There was no evidence of an effect on any clinical outcomes.

CONCLUSIONS

Our findings highlight discrepancies produced by the indiscriminate inclusion of studies with methodological flaws in previous systematic reviews. Regular weighing of pregnant women is futile in the absence of clinical benefit.

Effective interventions in preventing gestational diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

Lifestyle choices, metformin, and dietary supplements may prevent GDM, but the effect of intervention characteristics has not been identified. This review evaluated intervention characteristics to inform the implementation of GDM prevention interventions.

METHODS

Ovid, MEDLINE/PubMed, and EMBASE databases were searched. The Template for Intervention Description and Replication (TIDieR) framework was used to examine intervention characteristics (who, what, when, where, and how). Subgroup analysis was performed by intervention characteristics.

RESULTS

116 studies involving 40,940 participants are included. Group-based physical activity interventions (RR 0.66; 95% CI 0.46, 0.95) reduce the incidence of GDM compared with individual or mixed (individual and group) delivery format (subgroup p-value = 0.04). Physical activity interventions delivered at healthcare facilities reduce the risk of GDM (RR 0.59; 95% CI 0.49, 0.72) compared with home-based interventions (subgroup p-value = 0.03). No other intervention characteristics impact the effectiveness of all other interventions.

CONCLUSIONS

Dietary, physical activity, diet plus physical activity, metformin, and myoinositol interventions reduce the incidence of GDM compared with control interventions. Group and healthcare facility-based physical activity interventions show better effectiveness in preventing GDM than individual and community-based interventions. Other intervention characteristics (e.g. utilization of e-health) don't impact the effectiveness of lifestyle interventions, and thus, interventions may require consideration of the local context.

Effect of excessive gestational weight gain before and after 28 weeks on trial of labor after cesarean stratified by pre-pregnancy body mass index: a retrospective cohort study

This study aimed to assess the effect of excessive gestational weight gain (GWG) before and after 28 weeks on the mode of delivery in women who attempted a trial of labor after cesarean (TOLAC), stratified by pre-pregnancy BMI. A retrospective analysis of the outcomes of eligible women who attempted trial of labor after cesarean (TOLAC) in a Chinese hospital from January 2016 to October 2022 was performed. GWG before and after 28 weeks was categorized as 'excessive' or 'non-excessive' based on the guideline of Institute of Medicine (IOM). Multivariable logistic regression analyses were used to estimate the effect of excessive GWG before and after 28 weeks on mode of delivery in women who underwent TOLAC, stratified by pre-pregnancy BMI. Of the 512 women who underwent term trial of labor, 71.1% achieved a vaginal birth. No correlation was found between excessive GWG before 28 weeks and the rate of vaginal birth after cesarean (VBAC). Among women with or without excessive GWG before 28 weeks, excessive GWG after 28 weeks was significantly associated with a reduced rate of VBAC. When stratified by pre-pregnancy BMI, women who had excessive gestational weight gain after 28 weeks gestation had lower rates of VBAC than those who did not, regardless of being underweight, normal or overweight (aOR 0.23, 95% CI 0.06-0.88; aOR 0.42, 95% CI 0.25, 0.70; and aOR 0.12, 95% CI 0.04-0.36; respectively). Excessive weight gain after 28 weeks of pregnancy was related to decreased rates of VBAC, irrespective of pre-pregnancy weight status and weight gain before 28 weeks.

The effect of exercise on the prevention of gestational hypertension in obese and overweight pregnant women: An updated meta-analysis

Background

Gestational hypertension (GH) is a common disease that seriously threatens the safety and health of pregnant women and their newborns. Physical exercise (PE) is widely recognized as a health maintenance method and it has numerous benefits. Studies on the association between PE and the risk of GH in obese and overweight pregnant women have generated controversial findings. This updated meta-analysis was performed to reassess the effects of PE on GH.

Methods

The articles from inception to April 2022, presenting studies investigating exercise intervention and pregnancy outcomes were explored across several online databases. Heterogeneity among the included studies was estimated and tested by Q test and I ² statistic. Risk ratios (RRs) and 95% confidence intervals (CI) were calculated through either random-effect or fixed-effect models. Subgroup analyses, sensitivity analyses, and publication bias diagnoses were also conducted.

Results

Twelve with 1,649 subjects were included. PE was associated with a reduced risk of GH in obese and overweight pregnant women (Pooled RR = 0.58, 95% CI = 0.42-0.81, P = 0.001; I ² = 24.3%). Subgroup analysis found significant trends amongst Eastern countries (RR = 0.59, 95% CI = 0.36-0.96, P = 0.033). Sensitivity analysis suggested the results were stable. No publication bias was detected based on Begg's test and Egger's test.

Conclusion

PE was associated with reduced risk of GH in obese and overweight pregnant women, especially in Eastern countries. More well-designed studies are still needed to further elaborate on these associations.

Systematic review registration

CRD42022326183.