Mark Landon

Neonatal morbidity in pregnancy complicated by diabetes mellitus: Predictive value of maternal glycemic profiles

The relationship between glycemic control and perinatal outcome was assessed in a relatively uniform population of 75 White Class B through D pregnant diabetic women. All patients used glucose reflectance meter self-monitoring and performed a minimum of four determinations daily. Mean capillary blood glucose was calculated from a minimum of 16 weeks of determinations. Regression analysis confirmed a correlation between these values and third-trimester hemoglobin A1 (p less than 0.001). The study population was divided into two groups on the basis of mean capillary blood glucose values: group I, mean capillary blood glucose less than 110 mg/dl (43 patients) (mean = 96.8 +/- 7.1); group II, mean capillary blood glucose greater than 110 mg/dl (32 patients) (mean = 126 +/- 9.0). Of the 32 patients in group II, eight had mean capillary blood glucose greater than or equal to 130 mg/dl. The degree of maternal glycemic control appeared to affect perinatal outcome. At least one form of infant morbidity was present in 33% of group I infants compared with 53% of group II. Significant differences were observed for the incidence of hypoglycemia (p less than 0.05), macrosomia (p less than 0.05), and respiratory distress syndrome (p less than 0.01). One of six group I infants delivered at 35 to 36 weeks developed respiratory distress syndrome, compared with four of seven group II patients. The appearance of phosphatidylglycerol in amniotic fluid appeared delayed in group II patients at term. These data suggest that maintaining mean capillary blood glucose values less than 110 mg/dl may serve to reduce several major forms of morbidity in the infant of the diabetic mother. This information is helpful in establishing objectives for glycemic control in pregnant women using self-monitoring techniques.

Capillary blood glucose screening for gestational diabetes: A preliminary investigation

Home glucose monitoring with the use of reflectance meters is an important adjunct in the care of pregnant women with insulin-dependent diabetes. The accuracy of reflectance meters for the assay of capillary glucose specimens has been well documented. The present preliminary study was undertaken to determine the utility of outpatient screening for gestational diabetes mellitus with the use of a reflectance meter (Accu-Chek, Boehringer Mannheim Co.). One hundred twenty-five patients in our high-risk practice had a standard 50 gm glucose load at 26 to 28 weeks gestation. Capillary glucose values were measured on site with the Accu-Chek. Venous plasma glucose levels were measured by the central laboratory chemistry analyzer. While the laboratory (x) and meter (y) glucose determinations between the two sets of values were highly correlated (R = 0.89, p less than 0.001), there was a significant difference in their average values (x = 111.74, y = 136.35, p less than 0.0001). With the use of a receiver operator characteristic curve, a meter value of 160 mg/dl was determined as the optimal threshold for performing a 3-hour glucose tolerance test. The sensitivity and specificity with the use of a meter value of 160 mg/dl were 93% and 96%, respectively, for detecting an abnormal screening test in venous plasma (greater than or equal to 135 mg/dl). A total of 32 glucose tolerance tests were performed, with four patients included who had venous values less than 135 mg/dl. All eight patients with gestational diabetes mellitus were correctly identified. These data suggest that a glucose reflectance meter can be used for accurate outpatient screening of gestational diabetes mellitus. The potential advantages of capillary blood glucose screening include both cost and efficiency. Patients with abnormal screening values can be promptly identified and scheduled for a follow-up 3-hour glucose tolerance test.