Gestational diabetes: Risk of recurrence in subsequent pregnancies

Background: It is believed that gestational diabetes (GDM) tends to recur across subsequent pregnancies, but the extent to which GDM persists remains unknown.

Methods: We conducted a retrospective cohort study using the KPSC 1991-2008 Matched Perinatal records, including birth certificate, hospitalizations, outpatient physician encounter, and laboratory records. The study comprised of primiparous women with first two (n=69,818) and first three (n=14,226) singleton births linked to their consecutive pregnancies. Odds ratios (OR) were used to estimate the extent to which GDM recurs across subsequent pregnancies after adjusting for confounders.

Results: The incidence of GDM during the first, second, and third pregnancy were 50, 73, and 91 per 1,000 singleton births, respectively. Risks of GDM in the second birth among women with and without previous GDM were 44.8% and 5.3%, respectively (OR=14.6, 95% confidence interval [CI] 13.5-15.7). The risk of recurrence of GDM across the first three births was even stronger. The risk was highest when women had GDM in both prior pregnancies (OR=23.6, 95%CI 17.3-32.0), followed by GDM in the second, but not in the first (OR=15.5, 95%CI 12.7-18.9), and lastly among women with GDM in the first but not in the second (OR=8.2, 95%CI 6.3-10.8) pregnancy. Shorter interpregnancy interval confers 8-to17-fold increased recurrence risk of GDM. In general, these recurrence risks were higher among Hispanics and Asian/Pacific Islanders than Caucasian women.

Conclusions: Previous pregnancies complicated by GDM increases the risk of recurrence of GDM in subsequent pregnancies. Hispanics and Asian/Pacific Islanders have higher risks of recurrence as compared to Caucasians.