The GROW study will characterize glucose homeostasis, diabetes progression, and the impact of a Pacific-specific variant (rs373863828) in the CREBRF gene, which is known to protect against T2DM, on glucose metabolism during and after pregnancy.<h4>Methods</h4>We will establish a prospective cohort study of 350 pregnant women in American Samoa, enrolled in their first trimester and followed through 18 months postpartum. This evidence concerns the gene CREBRF and diabetes mellitus.