The effect of probiotic supplementation during pregnancy on pregnancy complications: An umbrella meta-analysis.

BACKGROUND: Previous studies have suggested that probiotics might help prevent pregnancy complications, although recent meta-analyses have shown inconsistent results. To address this, an umbrella meta-analysis was conducted to investigate the impact of probiotics on pregnancy complications. METHODS: PubMed and Scopus databases were systematically searched for relevant meta-analyses, spanning from their inception to April 2024. The primary outcomes of interest were risk of gestational diabetes (GDM) and preeclampsia, and the secondary outcomes were gestational weight gain, gestational age (GA) at delivery, and cesarean section. A random-effects model was utilized to combine relative risks (RR) and standardized mean differences along with their respective 95% confidence intervals (CI) for categorical and continuous outcomes, respectively. RESULTS: In total, 27 studies involving 83,817 participants were incorporated. Probiotics supplementation notably decreased GDM risk (RR = 0.71, 95% CI: 0.61-0.83) while raised the odds of preeclampsia (RR = 1.23, 95% CI: 1.07-1.42) and increased GA (standardized mean differences = 0.07, 95% CI: 0.02 to 0.11). Subgroup analyses supported the preventive effect on GDM across various study characteristics. High-quality studies confirmed the increased risk of preeclampsia with probiotic use. Increased GA was observed in studies of moderate quality, with lower doses and Lactobacillus and Bifidobacterium strains. Probiotics did not significantly impact cesarean section or gestational weight gain in both overall and subgroup analyses. CONCLUSION: Probiotics supplementation among pregnant women resulted in a notable reduction in the risk of GDM but an elevation in the risk of preeclampsia and an extension of GA.