Screening for gestational diabetes mellitus – Can we use the 50-g glucose challenge test of the previous pregnancy?

Aim: To assess the association between previous pregnancy glucose challenge test (GCT) result among non-diabetic women and the rate for gestational diabetes mellitus (GDM) in the subsequent pregnancy. Methods: Retrospective database study in a university affiliated medical center from 2005 to 2017. Women who had a singleton pregnancy and two consecutive deliveries in our medical center were included. GDM diagnosis was based on either National Diabetes Data Group or Carpenter and Coustan criteria. Univariate analysis was followed by multivariate logistic regression. Results: A total of 31,861 women were included. GDM incidence among the subsequent pregnancies was 2.1% (670 women). Parturients with GDM had higher mean GCT results in their previous pregnancy compared with parturients without GDM (127.5 ± 28 VS. 98.7 ± 24 mg/dl, p < 0.001). Women with GDMA2 had higher former GCT results than women with GDMA1 (135.9 ± 28 VS. 125.7 ± 27 mg/dl, p < 0.001). Positive association between GCT results in previous pregnancy and rates of GDM in the subsequent pregnancy was noted. Using a GCT value of 107 mg/dl (65th percentile), the area under the receiver-operating curve was 0.79. Conclusion: GCT results in previous pregnancy is associated with GDM incidence in the subsequent pregnancy. Future prospective studies are warranted to better delineate the best screening approach for this subset of patients.