Treatment of Gestational Diabetes and Maternal Risk of Diabetes after Pregnancy

Objective: To compare postpartum glucose tolerance between women treated for gestational diabetes (GDM) and those not treated.
Methods: Metabolic testing was performed at 3-months and 1-year postpartum in 599 women comprising the following gestational glucose tolerance groups: (I) normal glucose challenge test (GCT) and oral glucose tolerance test (OGTT) in pregnancy; (II) abnormal GCT with normal OGTT; (III) gestational impaired glucose tolerance; (IV) mild untreated GDM; and (V) severe treated GDM.
Results: Birthweight progressively increased across Groups I-IV, before falling steeply in treated GDM (p<0.0001). In contrast, at 3-months and 1-year, insulin sensitivity and beta-cell function progressively decreased across the 5 groups, mirrored by rising fasting and 2-hour glucose (all p<0.0001). Accordingly, prevalence of pre-diabetes/diabetes at 1-year increased in a stepwise manner across Groups I-V (2.8%, 9.6%, 13.5%, 21.5%, 32.6%; p<0.0001).
Conclusion: Treating GDM lowers birthweight but does not disrupt the association between gestational glycemia and maternal pre-diabetes/diabetes after pregnancy.