Utility of Screening Fasting Plasma Glucose and Glycated Hemoglobin to Circumvent the Need for Oral Glucose Tolerance Test in Women with Prior Gestational Diabetes

Abstract

Introduction: Our aim is to propose an evidence-based strategy for screening postpartum dysglycemia. Methods: This study included adult non-pregnant women who were diagnosed with gestational diabetes (GDM) using International Association of Diabetes in Pregnancy Study Group (IADPSG) criteria during their index pregnancy (2012–2019). Eligible participants underwent a concurrent oral glucose tolerance test (OGTT) and glycated hemoglobin (HbA1c) test. A detailed questionnaire documenting relevant personal and medical history was filled, and the relevant anthropometric parameters were recorded. Results: We evaluated data from 377 women at a mean (± SD) age of 32.1 ± 4.6 years and at a median duration of 15 (10–33) months following childbirth. Diabetes was diagnosed in 42 (11.1%) women. Use of a combination cutoff [fasting plasma glucose (FPG) ≥ 6.1 mmol/L or glycated hemoglobin (HbA1c) ≥ 6.0% (42 mmol/mol)] avoided OGTT in 80.9% of the study cohort, without missing the diagnosis of diabetes in any study subject. The diagnosis was missed in 2.4% of women with diabetes (and 0.3% of whole cohort) using only the FPG criterion (≥ 5.6 mmol/L) or HbA1c criterion [HbA1c ≥ 5.7% (39 mmol/mol)] alone. These tests avoided the need for an OGTT in 75.3% and 65.5% of women, respectively. Conclusions: The proposed strategies are likely to be both patient- and physician-friendly and have the potential to address several barriers for postpartum screening among women with prior GDM.