(158) Does fetal sex impact the risk of maternal diabetes 10-14 years after delivery?

Objective: Limited data suggest that male fetal sex is associated with worse maternal Beta-cell function in pregnancy and a possible increased risk of maternal diabetes after delivery. We examined the association between fetal sex and the risk of prediabetes or diabetes 10-14 years after delivery.

Study Design: This is a secondary analysis of data from the prospective Hyperglycemia and Adverse Pregnancy Outcome Follow-Up Study (HAPO FUS). The exposure was assigned fetal sex at birth (female as the reference). The primary outcome was having either prediabetes or diabetes assessed 10-14 years after the index pregnancy; secondarily, prediabetes and diabetes were assessed separately. Modified Poisson regression models were used and adjusted for baseline covariates at enrollment (study field center, maternal age, parity, family history of diabetes) as well as time from enrollment to follow-up. We secondarily assessed whether the association between fetal sex and diabetes or prediabetes varied by gestational diabetes (GDM) status (effect modification), and whether maternal insulin sensitivity at pregnancy enrollment and insulin resistance at 10-14 year follow-up differed by fetal sex.

Results: Of 3,976 individuals in the analytic sample, 16.7% developed GDM and 48.7% of infants were assigned female sex. At 10-14 years after delivery (median 11.6 years), 3.1% of individuals developed diabetes and 22.9% developed prediabetes. In adjusted analyses, the risk of diabetes or prediabetes did not differ by fetal sex (female vs. male: 24.9 vs. 25.5%; aRR: 1.02, 95% CI 0.90, 1.15) (TABLE). This association was similar regardless of GDM status (interaction p=0.59). There was also no association between fetal sex and maternal insulin sensitivity at enrollment or insulin resistance at 10-14 year follow-up.

Conclusion: There was no association between fetal sex and the risk of maternal diabetes or prediabetes 10-14 years after delivery. Further research is needed to better understand the possible impact of fetal sex on maternal Beta-cell function.