title: Women with a nondiagnostic 75 g glucose tolerance test but elevated HbA1c in pregnancy: an additional group of women with gestational diabetes.
abstract: We examined whether pregnant women with a normal glucose tolerance test (OGTT) by New Zealand (NZ) criteria, but elevated HbA1c are a clinically important group with gestational diabetes (GDM). Eighty women with a normal OGTT and HbA1c > 40 mmol/mol, compared with others with GDM, had a significantly higher BMI and were more likely Pacific. Pharmacotherapy was prescribed in 77.5%. Post-partum OGTT and HbA1c were abnormal in 9/43(20.9%) and 27/42(64.3%), respectively. In 1090 women being screened for GDM by OGTT, most women with GDM had an HbA1c ≤ 40 mmol/mol. In the 22.1% of women with an HbA1c > 40 mmol/mol, the OGTT was normal in 61.8%. For centres using HbA1c to screen for underlying prediabetes/diabetes, these data show that a result >40 mmol/mol identifies women who are likely to require pharmacotherapy. An OGTT is still recommended to diagnose GDM, but these data raise questions about a possible role for HbA1c in high risk women with a nondiagnostic OGTT.
authors.affiliation: National Women's Health, Auckland, New Zealand.
authors.forename: Janet A
authors.initials: JA
authors.lastname: Rowan
authors.forename: Astrid
authors.initials: A
authors.lastname: Budden
authors.forename: Lynn C
authors.initials: LC
authors.lastname: Sadler
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D015992:Body Mass Index; D016640:Diabetes, Gestational / Q000175:diagnosis* / Q000208:ethnology; D005260:Female; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D009520:New Zealand; D011247:Pregnancy
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human
keywords: HbA1c; gestational diabetes; glucose tolerance test; obesity