Gestational diabetes: a red flag for future Type 2 diabetes in pregnancy? A retrospective analysis

AIMS: This study sought to understand the relationship between Type 2 diabetes in pregnancy and previous gestational diabetes (GDM), and determine whether a previous pregnancy with GDM was associated with subsequent better pregnancy planning. METHODS: A retrospective review of medical records of women with Type 2 diabetes in pregnancy was conducted at three teaching hospitals to ascertain whether they had earlier GDM, and to determine whether this is associated with differences in measures of pregnancy planning and diabetes management. RESULTS: Of 172 index pregnancies affected by Type 2 diabetes, in 76 (44%) cases, the mother had a previous history of GDM. Within this cohort, a diagnosis of 'overt diabetes in pregnancy', made on the basis of a GTT result during pregnancy in the WHO diabetic range with persistent diabetes post partum, was more common among women who had previous GDM than women who had not had GDM (20% vs 7%, P = 0.02). Women who previously had GDM did not exhibit a higher incidence of preconception planning or folate supplementation. CONCLUSIONS: It is common for women with Type 2 diabetes in pregnancy to have had GDM previously. The diagnosis of GDM is an opportunity to improve future pregnancy planning and outcomes for women with Type 2 diabetes in pregnancy. This goal is yet to be realized.