Impact of earlier gestational diabetes screening for pregnant people with obesity on maternal and perinatal outcomes

Abstract

Abstract Objectives Gestational diabetes (GDM) screening at 24–28 weeks’ gestation reduces risk of adverse maternal and perinatal outcomes. While experts recommend first-trimester screening for high-risk patients, including those with obesity, data supporting this recommendation is limited. Methods We implemented a systematic population intervention to encourage first-trimester GDM screening by oral glucose tolerance testing in a cohort of pregnant people with obesity in two integrated health systems from 2009 to 2013, and compared outcomes to the same population pre-intervention (2006–2009). Up to five years of postpartum glucose testing results (through 2018) were assessed among GDM cases in the post-intervention group. Primary outcomes were large-for-gestational-age birthweight (LGA); macrosomia; a perinatal composite outcome; gestational hypertension/preeclampsia; cesarean delivery; and medication treatment of GDM. Results A total of 40,206 patients (9,156 with obesity) were screened for GDM; 2,672 (6.6%) were diagnosed with GDM. Overall, multivariate adjusted risk for LGA and cesarean delivery were lower following the intervention (LGA: aOR 0.89 [0.82, 0.96]; cesarean delivery: 0.89 [0.85, 0.93]). This difference was more pronounced in patients diagnosed with GDM (LGA: aOR 0.52 [0.39, 0.70]; cesarean delivery 0.78 [0.65, 0.94]); insulin/oral hypoglycemic treatment rates for GDM were also higher post-intervention than pre-intervention (22 vs. 29%; p<0.0001). There were no differences for the other primary outcomes. Only 20% of patients diagnosed with GDM early in pregnancy who had postpartum testing had results in the overt diabetes range, suggesting a spectrum of diabetes detected early in pregnancy. Conclusions First trimester GDM screening for pregnant people with obesity may improve GDM-associated outcomes.