A single abnormal value of the glucose tolerance test is related to increased adverse perinatal outcome

Objective. To evaluate which pregnant women with a single abnormal value in the oral glucose tolerance test are at increased risk for adverse perinatal outcome. Methods. In this retrospective cohort study, we have evaluated the course of pregnancy in 152 consecutive women with only one abnormal value (OAV), and 624 with a 100 g - glucose tolerance test totally within the range values. Results. The prevalence of caesarean delivery, hypertensive disorders and macrosomia. was higher in the study group when compared with the control group, whereas no difference was noted concerning gestational age at delivery, Apgar score at 1 and 5 min and neonatal hypoglycemia. Moreover, in the study group hypertensive disorders were more frequent in the subgroup with the elevated value at 1 h after the glucose load (25%), whereas macrosomia is more frequent when it is the fasting value to be elevated (29.7%). Conclusions. Our results show that the implications of a single elevated glucose tolerance test value vary in relation to the timing of the abnormal value. In fact, OAV fasting or 1-h after load has a higher prevalence for an adverse obstetric outcome, whereas a 2 or 3-h value does not present significant differences when compared with the control group.