Gestational diabetes mellitus (GDM) is a common pregnancy complication, and alterations in fatty acid (FA) metabolism have been proposed as a contributing factor. However, evidence regarding individual circulating FAs has remained inconclusive. A systematic review and meta-analysis published in Diabetes & Metabolic Syndrome: Clinical Research & Reviews compared circulating FA profiles between pregnant women with and without GDM and evaluated their associations with GDM risk.

PubMed, Scopus, and Web of Science were searched for observational studies reporting circulating FAs in relation to GDM. Random-effects models were used to calculate pooled standardized mean differences (SMDs) and odds ratios (ORs). Subgroup analyses examined sources of heterogeneity, and the Newcastle–Ottawa Scale assessed risk of bias.

Each one-standard deviation increase in palmitic acid (C16:0) was associated with higher odds of GDM (OR 1.20; 95% confidence interval [CI] 1.04-1.38). In contrast, very-long-chain saturated FAs (C22:0 and C24:0) and omega-6 FAs, including linoleic acid (C18:2), C20:2, and C22:4, were associated with lower odds. SMD analyses showed significantly lower circulating levels of C22:0, C15:0, and C17:0 in women with GDM.

Fatty acid form, such as free FAs versus phospholipids, was identified as a heterogeneity source for eight FAs, measurement unit for three FAs, and risk of bias, study design, and trimester for limited specific FAs. Overall, GDM was associated with distinct circulating FA patterns, with C16:0 linked to higher odds and linoleic acid, very-long-chain saturated FAs, and selected omega-6 FAs associated with lower odds.