Cut‐off value of 1‐h, 50‐g glucose challenge test for screening of gestational diabetes mellitus in an Iranian population

Abstract

This study aimed to investigate the cut-off value of the glucose challenge test in an Iranian population. A total of 1804 consecutive native Iranian women who underwent a glucose challenge test were prospectively investigated. The test was performed between 24 and 28 weeks of gestation; each subject received a 50-g oral glucose load regardless of her fasting or fed state; the 1-h venous plasma glucose level was then determined. Women exceeding 130 mg/dl received the diagnostic 100-g, 3-h oral glucose tolerance test to determine whether or not they had gestational diabetes mellitus. The prevalence of the glucose challenge test for the whole cohort was 7.2%. The receiver-operator characteristic curve identified a glucose challenge test finding above 135 mg/dl as the cut-off value for detecting gestational diabetes mellitus, which showed a sensitivity and specificity of 95% and 80%, respectively. Our results suggest that the cut-off value of a 50-g glucose challenge test is 135 mg/dl to identify pregnancies with gestational diabetes mellitus in an Iranian population.