BLOOD-GLUCOSE LIMITS IN THE DIAGNOSIS OF IMPAIRED GLUCOSE-TOLERANCE DURING PREGNANCY - RELATION TO MORBIDITY

Objective. To evaluate the accuracy of diagnosing gestational diabetes mellitus (GDM) by a 2-h blood glucose value greater than or equal to 9.0 mmol/1 in the 75 g oral glucose tolerance test (OGTT). The maternal and neonatal outcome in women with a 2-h blood glucose value just below this limit, 8.0-8.9 mmol/1, is analyzed. The outcome is compared to a randomly selected control group. Design. A comparative study. Subjects. There were 223 women in the group with a 2-h value of 8.0 to 8.9 mmol/1 in the OGTT This group was compared to a randomly selected control group of 391 women. Main outcome measures. Fetal outcome: perinatal mortality, birth weight, respiratory disturbances, symptomatic hypoglycemia, polycythemia, hyperbilirubinemia and traumatic deliveries. Maternal age, body mass index (BMI), pregnancy-induced hypertension (PIH) or preeclampsia and route of delivery. Results. The women in the group with a 2-h glucose value of 8.0-8.9 mmol/1 were, compared to the control group, significantly older, heavier, had a higher BMI, gave birth to heavier children and a significantly increased number of large-for-date infants, while there were no differences in neonatal mortality, morbidity or birth trauma. Conclusions. This study shows that using the 75 g 2-h OGTT with a B-glucose limit of greater than or equal to 9.0 mmol/1 instead of greater than or equal to 8.0 mmol/1 to diagnose GDM during pregnancy has no major adverse effects concerning maternal and neonatal outcome in the borderline interval of 8.0 to 8.9 mmol/1.