Objective: Gestational diabetes mellitus (GDM) is a common pregnancy complication with adverse maternal and neonatal consequences. Probiotics have been proposed as a non-pharmacological intervention, but their effectiveness remains controversial. This study aimed to evaluate the methodological quality and reported efficacy evidence of systematic reviews and meta-analyses (SRs/MAs) on probiotic supplementation in pregnant women with GDM. Methods: Four electronic databases were searched for English-language SRs/MAs published between 2017 and 2024 that examined probiotic supplementation in women with GDM. Methodological quality was assessed using PRISMA 2020, AMSTAR 2, and ROBIS, and reported efficacy outcomes were systematically synthesized. Results: A total of 16 SRs/MAs were included. According to the AMSTAR-2 assessment, four studies were rated as low quality, while the remaining studies were rated very low. The PRISMA assessment showed that 8 of the 27 items had reporting completeness above 80%, whereas items 5, 8, and 22 showed completeness below 60%; at the study level, 12 SRs/MAs achieved overall PRISMA reporting completeness above 80%. The ROBIS scale assessment results showed that all SRs/MAs were rated as low risk of bias in Phase 1, Domain 1, Domain 3, and six items of Domain 4, as well as 12 items in Phase 3. However, in Domain 2, all SRs/MAs were rated as high risk. Regarding efficacy evaluation, probiotic supplementation significantly improved FPG, insulin-related indices (FSI, HOMA-IR, HOMA-B, QUICKI), and lipid profiles (TG, TC, HDL-C, VLDL-C). In addition, probiotics showed effects on markers of inflammation (CRP) and oxidative stress (NO, MDA, GSH, TAC) and indicated benefits in reducing neonatal risks. However, heterogeneity and overlap among primary studies were identified. Conclusion: Probiotic supplementation demonstrates efficacy in improving metabolic biomarkers related to GDM and maternal and neonatal outcomes. Nevertheless, the overall certainty of evidence is limited by suboptimal methodological quality, heterogeneity, and overlap among primary studies. Keywords: gestational diabetes mellitus, probiotic, pregnant women, meta-analysis, overview
Ren et al. (Sun,) studied this question.