FROM OBSTETRICS & GYNECOLOGY
(FRONTLINE MEDICAL NEWS) In women with prior mild gestational diabetes, subsequent pregnancies did not increase the frequency of metabolic syndrome but did increase the risk of type 2 diabetes, according to a review of 426 women 5-10 years after a GDM pregnancy.
The risk of diabetes was greatest if additional pregnancies were also complicated by mild gestational diabetes mellitus (GDM).
The investigators assessed women 5-10 years after they participated in a mild GDM treatment study . The goal was to assess the impact of subsequent pregnancies on cardiometabolic risks. GDM is a known risk factor for type 2 diabetes and metabolic syndrome, but it hasn’t been clear until know how subsequent pregnancies influence the risk, said investigators led by Michael Varner, MD, a professor at the University of Utah School of Medicine, Salt Lake City ( Obstet Gynecol 2017;129:273-80 ).
Echoing previous studies of mild GDM, about a third of the women had metabolic syndrome at follow-up, but the number of subsequent pregnancies didn’t seem to make a difference. Among the 212 women with no additional pregnancies, 34% had metabolic syndrome; among the 143 with one pregnancy, 33% had metabolic syndrome; and among the 71 with two or more, 30% had metabolic syndrome, as defined by American Heart Association and National Heart, Lung, and Blood Institute criteria .
“Although we observed a high overall frequency of metabolic syndrome in our cohort, our data suggest that subsequent pregnancies do not increase a woman’s risk of developing metabolic syndrome,” Dr. Varner and his colleagues said.
However, subsequent pregnancies did affect diabetes risk; 5.2% of women with no additional pregnancies had diabetes at follow-up, versus 10.5% of women with one additional pregnancy and 11.3% of those with two or more. The risk of diabetes was greatest if a subsequent pregnancy was complicated by GDM (relative risk, 3.75; 95% confidence interval, 1.60-8.82), as was the case for about a third of the women who had additional pregnancies.
“The association with diabetes was driven mostly by subsequent pregnancy complicated with GDM,” the investigators said.
The findings “could be consistent with either a stronger genetic or an environmental predisposition to type II diabetes, [but] could also represent confounders that were not measured in this prospective observational follow-up study. … Our data are limited … by the fact that we do not know how many patients had metabolic syndrome at the time of the index pregnancy,” they said.
At follow-up during Feb. 2012-Sept. 2013, women with no additional pregnancies were a median 38 years old; women who had one pregnancy were a median of 35 years, and those with two or more a median of 33 years. The interval from participation in the parent study to participation in the follow-up study was 7 years in women with no or one additional pregnancy, and 8 years for women with two or more. There were no other significant differences among the groups. The average body mass index was about 29 kg/m2; 59% of the women were Hispanic.
The National Institutes of Health funded the work. The authors had no disclosures.
