Comparison of postprandial 90th-minute plasma glucose level with 60th- and 120th-minute levels in patients with gestational diabetes: a prospective cohort study

PURPOSE The objective of the present study is to compare postprandial 90th-minute plasma glucose measurement with fasting, postprandial 60 and 120 min in gestational diabetes mellitus (GDM). METHODS One hundred and thirty-one pregnant women with GDM were hospitalized for regulation of maternal plasma glucose levels. Plasma glucose levels were daily recorded for every patient and treatment option arranged without considering the 90th-minute plasma glucose level. All patients were followed up until birth and pregnancy results were compared. RESULT At the admission, 69% of our patients were on diet and 31% were on insulin with diet therapy. The highest postprandial mean plasma glucose was seen at 90 min after breakfast (137.50 mg/dl), at 60 min after lunch (137.80 mg/dl), and 60 min after dinner (134.50 mg/dl). The cut-off level for postprandial glucose at 90th minute was determined as 130 mg/dl. The upper limit plasma glucose levels were most frequently exceeded at 90th minute for each meal. High plasma glucose levels and the need for neonatal intensive care unit were correlated (p < 0.05). CONCLUSIONS The highest plasma glucose level was seen at 90 min after breakfast, 60 min after lunch, and 60 min after dinner. The upper limit plasma glucose levels were most frequently exceeded at the 90 min.