PAPPA and gestational diabetes: The pooled MD for PAPP-A was lower, although not significantly, for women who were diagnosed with GDM later in pregnancy (24–28 weeks gestation) than women who were diagnosed early in pregnancy (<24 weeks gestation) compared to normoglycemic women (MD -0.19; 95% CI -0.27, -0.11 vs. MD -0.14; 95% CI -0.24, -0.05; p = 0.41) (S6 Fig).