The after breakfast 50-g, 1-hour glucose challenge test in urban Mexican pregnant women: Its sensitivity and specificity evaluated by three diagnostic criteria for gestational diabetes mellitus

Background To study the sensitivity and specificity of the 50-g, I-hour ges tational glucose challenge lest performed 1 to 2 hours after a non-standard ized home breakfast in urban Mexican women by using three different gestati onal diabetes mellitus diagnostic criteria. Methods. Four hundred and forty-five consecutive women of 24-28 weeks gesta tion were studied. The glucose challenge test was performed in the fed stat e and a week later a fasting 100-g, 3-hours oral glucose tolerance test was carried out in all of them. Duplicate serum glucose concentrations were de termined by a glucose-oxidase method. Sensitivity and specificity were calc ulated using three different diagnostic criteria for gestational diabetes m ellitus. Results. The glucose challenge test performed as indicated, with a cutoff o f 7.8 mmol/L, had 88-89% sensitivity and 85-87% specificity when using as d iagnostic criteria those proposed by the National Diabetes Data Group and b y Carpenter & Coustan; by using Sacks et al. criteria, the values were 82% and 88%, respectively. Considering only pregnant women greater than or equa l to 25 years of age, the sensitivity increased to 92% with the National Di abetes Data Group criteria. Pregnant women <25 years of age had significant ly lower blood glucose values than those with age greater than or equal to 25 years during the glucose tolerance test. Conclusions. For the general group the sensitivity of the glucose challenge test performed 1 to 2 hours after breakfast was similar, based on the Nati onal Diabetes Data Group and the Carpenter & Coustan's diagnostic criteria for gestational diabetes mellitus. However, when pregnant women greater tha n or equal to 25 years of age were considered, the use of the former criter ia yielded a slightly better sensitivity.