Predictors of Completion of Postpartum Diabetes Screening among Patients with Gestational Diabetes

Despite the high lifetime risk of developing diabetes after gestational diabetes mellitus (GDM), postpartum completion of glucose tolerance testing (GTT) is disappointingly low, less than 50%. This study aimed to identify patient, obstetric, prenatal, and social factors associated with the likelihood of completing a postpartum GTT test. This retrospective study of 515 singleton pregnancies diagnosed with GDM used logistic regression to examine engagement in prenatal care, social determinants of health, and medical/obstetric factors impacting the completion of postpartum 2-hour GTT. About 46.3% of the cohort completed postpartum GTT. Each prenatal visit increased the odds of postpartum GTT by 7% (CI: 1.01,1.14). Black patients had 60% (CI: 0.23, 0.70) lower odds of postpartum GTT compared with White patients, and Hispanic patients had 53% (CI: 0.39, 0.72) lower odds compared with non-Hispanic patients. Patients with commercial insurance had 2.4 times (CI: 1.59, 3.72) the odds of postpartum testing compared with publicly insured patients. Those with chronic hypertension had 69% decreased odds compared with patients without (CI: 0.12, 0.85), and patients with preeclampsia had 52% lower odds compared with those without (CI: 0.25, 0.94). Our data demonstrate that less than 50% of our population completed postpartum GTT. The number of prenatal visits and a shorter interval between screening and diagnostic testing are key predictors of postpartum follow-up, and social determinants of health were significant risk factors for not following up. This study identified a broad spectrum of factors potentially associated with postpartum GTT completion, and its exploratory nature paves the way for further analyses that mitigate confounding and better elucidate the reasons for the gap in care.