Decreased maternal serum inhibin-A in pregestational diabetic women implication for adjustment

OBJECTIVE: To evaluate the effect of maternal pregestational diabetes on serum dimeric inhibin-A (DIA), 1 of the 4 markers of the quadruple screen. STUDY DESIGN: The data were collected retrospectively from women with singleton pregnancies who had a quadruple screen drawn at 15-20 weeks of gestation in 2004-2006. A total of 84 women with pregestational diabetes were identified and their DIA values were compared with those of 100 nondiabetic pregnant women. We compared the mean multiples of the median (MoM) for DIA levels among diabetics, among nondiabetics and between the 2 types of diabetics. We also measured the degree of correlation between the quadruple screen markers and glycosylated hemoglobin (HbA1C). RESULTS: The corrected mean MoM for DIA levels among diabetic patients was 0.85 (95% CI, 0.77-0.95) vs. 1.0 (95% CI, 0.93-1.09) in the nondiabetic control group (p = 0.02). The mean MoM for DIA levels did not appear to differ between type 1 and type 2 diabetes, and there does not appear to be a correlation between the quadruple screen markers and HbA1C. CONCLUSION: The DIA levels among pregestational diabetic women are lower than in the nondiabetic population, suggesting a need for adjustment.