We explored the association between gestational age and T2DM in 5-year intervals following first pregnancy (Figure
2). In the first decade after very preterm birth, there was no increased risk of T2DM compared with term birth.
However, there was an inconsistent change in risk in the second decade, which reached statistical significance. No
significant associations were found after 21 years following first pregnancy among women with a very preterm birth. In
contrast, women who had a moderate preterm birth had significant, roughly two-fold, increased risk of T2DM for the
first 10 years after their first pregnancy, which thereafter returned to the baseline risk of women who had delivered at
term. Postterm birth did not appear to be associated with T2DM at any time period.