Fasting glucose in the first trimester: An initial approach to diagnosis of gestational diabetes

• Published in: Endocrinología, diabetes y nutrición. diabetes y nutrición., 2019-01, Vol.66 (1), p.11-18
• Main Authors: López del Val, Teresa, Alcázar Lázaro, Victoria, García Lacalle, Concepción, Torres Moreno, Beatriz, Castillo Carbajal, Gabriela, Alameda Fernandez, Beatriz
• Format: Article
• Language: English
• Subjects: Diabetes gestacional; Embarazo; Endocrinology and Metabolism; Fasting glucose in the first trimester; Gestational diabetes mellitus; Glucemia basal primer trimestre; Oral glucose tolerance test; Pregnancy; Sobrecarga oral de glucosa
• ISSN: 2530-0180; 2530-0180
• DOI: 10.1016/j.endien.2019.01.001

Abstract Objectives To establish whether fasting glucose levels in the first trimester (FGFT) of pregnancy ≥92 mg/dl (5.1 mmol/l) (FGFT) anticipate the occurrence of maternal-fetal complications of gestational diabetes mellitus. To assess whether FGFT can replace diagnosis of GDM using the classical two-step oral glucose tolerance test (OGTT). Methods A retrospective study of 1425 pregnancies with FGFT and O'Sullivan Test (OST) and/or OGTT according to OST results in the second trimester. FGFT sensitivity and specificity were assessed as compared to the conventional diagnosis of GDM. The relationship between maternal-fetal complications and FGFT was assessed in the total group and after excluding mothers who received specific medical treatment for GDM. Results Sensitivity and specificity of FGFT levels ≥92 mg/dl were 46.4% and 88.8% as compared to diagnosis of GDM using Carpenter and Coustan criteria. In the total group, a statistically significant relationship was found between FGFT levels ≥92 mg/dl and newborn weight (3228 ± 86 versus 3123 ± 31 g; p < 0.05), as well as a higher rate of macrosomia (6.9% versus 3.5%; p < 0.05). This association persisted after excluding patients diagnosed with and treated for GDM (weight: 3235 ± 98 versus 3128 ± 31 g; p < 0.05; percentage of macrosomia: 7.2% versus 3.4%; p < 0.05). Conclusions FGFT is not a good substitute for conventional diagnosis of GDM in the second trimester. Pregnant women with FGFT levels ≥92 mg/dl, even with no subsequent diagnosis of GDM, are a risk group for fetal macrosomia and could benefit from dietary measures and physical exercise.