Sun C, Wu QJ, Gao SY, et al. - Via searching relevant databases on Embase, PubMed, Cochrane Library and Web of Science before May 10, 2019, researchers explored the connection between ferritin and the risk of gestational diabetes mellitus (GDM). Using a random effects model, the relative risks and 95% confidence intervals of GDM risk have been summarized. A total of 10 studies have been reported involving 4,690 candidates. Data reported that the summary relative risk contrasting individuals with the highest concentration categories of ferritin with the lowest concentration categories of ferritin was 1.87. According to this meta-analysis, increased ferritin levels were related to an increased risk of GDM. However, further prospective cohort studies to confirm the results were needed, particularly the dose-response link between ferritin and GDM. There was no evidence of bias in publishing.