Abstract
Objective
To examine the relationship between periconceptional folate exposure and risk of gestational diabetes mellitus (GDM).
Methods
Several electronic databases, including PubMed, Embase, China National Knowledge Infrastructure (CNKI), China Biology Medicine (CBM), and Cochrane Library, were searched for all relevant cohort studies by January 2021. Studies on relationship between folate exposure (intake or status) and GDM risk were included. Quality of included studies was assessed using Newcastle-Ottawa Scale. Random effects meta-analysis was performed to estimate overall odds ratio (OR) and 95% confidence intervals (CIs) by Stata software (Stata Corp., College Station, TX).
Results
Ten cohort studies with 40,244 pregnancies were eligible for quantitative meta-analysis. Significant association was observed between folate exposure and risk of GDM (OR = 1.24, p=.036, 95% CI: 1.01–1.52). Subgroup analysis revealed that periconceptional folate exposure of population in China (OR = 1.35, 95% CI: 1.09–1.67) but not in western countries, folate exposure during pregnancy (OR = 1.49, 95% CI: 1.22–1.81) but not before pregnancy, and internal folate exposure (OR = 1.36, 95% CI: 1.10–1.67), were significantly associated with increased GDM risk.
Conclusions
Overall, periconceptional folate exposure is positively associated with GDM risk, especially the exposure during pregnancy and exposure in Chinese populations.
Acknowledgements
The authors acknowledge authors of the studies included in this report, especially Nianhong Yang (Huazhong University of Science and Technology) and Qiong Wang (Sun Yat-sen University) for their data sharing.
Disclosure statement
The authors declare no conflict of interest.