FABP4 and gestational diabetes: Nevertheless, circulating FABP4 and OC concentrations in GDM cases proved to surpass those detected in healthy controls (FABP4, SMD = 2.99, 95% CI, 2.28–3.69, P < 0.01; Fig. 2a; OC, SMD = 0.68, 95% CI, 0.31–1.05, P < 0.01; Fig. 2e).