The Association Between Chemerin Levels and Gestational Diabetes Mellitus: An Updated Systematic Review and Meta-Analysis.

Chemerin is an adipokine that is associated with insulin resistance, a feature well marked in gestational diabetes mellitus (GDM). Recent publications and meta-analyses investigating chemerin levels in GDM remain inconclusive. This updated systematic review and meta-analysis aims to update the current evidence of an association between chemerin and GDM. The databases PubMed, ScienceDirect, and Google Scholar were searched for eligible articles from their inception up to 1 April 2025. Pooled standardized mean differences (SMDs) and 95% confidence intervals (CIs) of the chemerin levels between GDM cases and normoglycemic controls were calculated using the "meta" package in "R" software. Twenty-two studies were included in this meta-analysis, comprising a total of 1735 GDM cases and 1701 normoglycemic pregnant controls. Due to significant heterogeneity, a random effects model was applied, and the chemerin levels were found to be significantly higher in cases compared to normoglycemic controls [SMD = 0.97, 95% CI (0.16; 1.78) ng/mL; p = 0.020]. Subgroup analysis showed that studies conducted in Asia, studies utilizing a case-control design, patients younger than 30 years, and patients with a BMI less than 28 showed significantly higher chemerin levels in cases compared to controls. Meta-regression analysis indicated that only patients over 30 years old showed a negative association with chemerin levels. No evidence of publication bias was observed. This updated meta-analysis confirmed that chemerin levels are elevated in cases of GDM, which may indicate its involvement in the pathogenesis of GDM. Further longitudinal studies are needed to consolidate this finding.