Persistent organic pollutant exposure as a risk factor of gestational diabetes mellitus: A systematic review and meta-analysis

Abstract

Background: Findings related to the association between persistent organic pollut- ants (POPs) and gestational diabetes mellitus (GDM) are inconclusive. Objectives: To estimate the strength of the association between POP exposure and GDM in a systematic review with meta-analysis. Search strategy: MEDLINE, Scopus and Web of Science were searched until July 2023. Selection criteria: Cohort and case–control studies analysing the association be- tween POPs and GDM. Data collection and analysis: We assessed the risk of bias using the Quality in Prognosis Studies scale (QUIPS). Standardised mean differences were pooled using random-effect models. Main results: Sixteen articles including 12 216 participants were selected. The risk of bias was high in four articles (25%), moderate in 11 (68.75%) and low in one (6.25%). Small mean difference between GDM cases and controls was observed for PFHpA (0.26, 95% confidence interval [CI] 0.1–0.35, I2 = 0.0%), PCB180 (0.37, 95% CI 0.19–0.56; I2 = 25.3%), BDE47 (0.23, 95% CI 0.0–0.45, I2 = 0%), BDE99 (0.36, 95% CI 0.14–0.59; I2 = 0%), BDE100 (0.42, 95% CI 0.19–0.64; I2 = 0%) and HCB (0.22, 95% CI 0.01–0.42, I2 = 39.6%). No considerable difference was observed for the rest of POPs. Conclusion: Small mean differences between GDM cases and controls were ob- served for some POPs. However, evidence shows mostly moderate quality and results were heterogeneous. Improved research methodology is needed to assess POPs and GDM risk.