INS and gestational diabetes: The Gen3G cohort has many unique characteristics including recruitment in the first weeks of pregnancy, comprehensive metabolic phenotyping during pregnancy including screening for prepregnancy diabetes (based on A1c and 50 g glucose challenge test) and GDM (with 75 g-oral glucose tolerance test (OGTT) and collection of additional maternal plasma samples), multiple metabolic biomarkers (eg, insulin, lipids, adipokines) and the collection of cord blood and placenta samples (all described in prior cohort profile9).