Modifiable risk factors for gestational diabetes recurrence

The literature on risk factors for gestational diabetes mellitus recurrence is inconsistent and sometimes contradictory. The importance of inter-pregnancy interval and parity, remains unclear. We aimed to explore controversial risk factors for gestational diabetes mellitus recurrence, especially the modifiable ones, and to develop a prediction model in a cohort of women with gestational diabetes mellitus. A retrospective, population-based, cross-sectional cohort study was performed. The study included 788 women with gestational diabetes mellitus that delivered between 1991-2012 and had consecutive deliveries at a university affiliated hospital in Israel. Women with pre-existing diabetes were excluded. Factors associated with gestational diabetes mellitus recurrence were examined using log-binomial models to estimate prevalence ratios with 95 % confidence intervals. Multivariate analysis revealed that both inter-pregnancy interval and multiparity were significant risk factors for gestational diabetes mellitus recurrence. Other significant risk factors were maternal age, gestational diabetes mellitus diagnosis week, oral glucose tolerance test values, body mass index gain between pregnancies and insulin use; the latter and multiparity had the strongest effect size (PR ≥ 1.2). Among multiparous women, the association between inter-pregnancy interval and gestational diabetes mellitus recurrence was significantly lower (P = 0.0004) compared with primiparous women (PR = 1.11 [95 % CI 1.09-1.13] versus PR = 1.17 [95 % CI 1.15-1.20], respectively). The model we developed, predicts that reducing the inter-pregnancy interval and weight gain between pregnancies can reduce substantially the risk of gestational diabetes mellitus recurrence. The results suggest that weight gain and inter-pregnancy interval are modifiable risk factors for gestational diabetes mellitus recurrence. Our model could assist physicians in advising women with gestational diabetes mellitus in reducing the risk of recurrent gestational diabetes mellitus during subsequent pregnancies.