Objective
To assess the association of subsequent pregnancy with subsequent metabolic syndrome and type II diabetes mellitus after a pregnancy complicated by mild gestational diabetes mellitus (GDM).
Methods
We conducted a prospective observational follow up study of women with mild GDM randomized from 2002–2007 to usual care or dietary intervention and glucose self-monitoring. Women were evaluated 5–10 years after the parent study. Participants were grouped according to the number of subsequent pregnancies (Group A, none [reference]; Group B, one; Group C, ≥ two). Serum triglycerides, glucose tolerance, HDL-cholesterol, blood pressure, and waist circumference were assessed. Metabolic syndrome was diagnosed by American Heart Association and National Heart Lung and Blood Institute criteria. Multivariable regression was used to estimate adjusted relative risks (RR) and 95% confidence intervals (CI).
Results
Of 905 eligible women from the original trial, 483 agreed to participate, 426 of whom were included in this analysis. Groups A, B, and C consisted of 212, 143, and 71 women, respectively. Of women with subsequent pregnancies, 32% (69/214) had another pregnancy complicated with GDM. No difference between groups was observed for metabolic syndrome (Group A, 34%; Group B, 33%; Group C, 30%). Subsequent pregnancies were associated with diabetes mellitus outside of pregnancy (Group A, 5.2%; Group B, 10.5%, RR 2.62, 95%CI 1.16–5.91; Group C, 11.3%, RR 2.83, 95%CI 1.06–7.59), and if complicated with GDM (no subsequent GDM pregnancy, RR 1.99, 95%CI 0.82–4.84; subsequent GDM pregnancy, RR 3.75, 95%CI 1.60–8.82).
Conclusions
In women with prior mild GDM, subsequent pregnancies did not increase the frequency of metabolic syndrome, but subsequent pregnancies with GDM increased the risk of diabetes mellitus outside of pregnancy.