Predictive association between early pregnancy IGFBP1 levels and GDM incidence were replicated in a nested case–control study in the MOMS cohort (n = 55 GDM cases, diagnosed based on Carpenter–Coustan criteria at a median of 29 weeks gestation; matched 1:2 with noncases): the OR was 0.40 (95% CI, 0.24–0.67; P < 0.001, adjusted for maternal age and BMI) per s.d. increase in plasma IGFBP1 (measured at a median of 17 weeks gestation). Here, IGFBP1 is linked to gestational diabetes.