Do HbA1c levels and the self-monitoring of blood glucose levels adequately reflect glycaemic control during pregnancy in women with type 1 diabetes mellitus?

AIMS/HYPOTHESIS: Pregnancies of women with type 1 diabetes mellitus are associated with maternal and perinatal complications. These complication rates remain elevated despite achievement of the treatment goals described in the widely used guidelines of the American Diabetes Association (i.e. HbA(1)c level 7.0%. Self-monitored glucose levels and those measured with CGMS were compared between patients with four or five, six to nine and ten or more SMBG determinations daily. RESULTS: In patients with HbA(1)c levels 6.0%. In women with HbA(1)c levels 6.0-7.0% and >7.0%, these levels did not differ. The detection rate of hyper- and hypoglycaemic episodes was significantly higher in patients with ten or more SMBG determinations daily than in patients with fewer than ten. CONCLUSIONS/INTERPRETATION: Treatment of diabetes in pregnant women should be aimed at achieving HbA(1)c levels within the normal range, i.e.

Sibling birthweight as a predictor of macrosomia in women with type 1 diabetes.

AIMS/HYPOTHESIS: The aim of this study was to establish the value of maternal HbA1c levels and older sibling birthweight as predictors of birthweight and macrosomia in the offspring of women with type 1 diabetes. SUBJECTS AND METHODS: A total of 214 pregnancies of 107 women with type 1 diabetes were studied. Regression analysis was performed to test the predictive value of the birthweight of the first-born infant, HbA(1)c levels, maternal BMI, maternal age and time between subsequent births on the birthweight of the second-born infant. Birthweights were corrected for sex and gestational age. The percentages of first- and second-born infants with macrosomia (weight >90th centile) were calculated and compared. RESULTS: Only the birthweight of earlier born infants was significantly related to that of second-born infants (p<0.001) and 40-50% of the variation in the birthweight of second-born infants could be explained by the birthweight of the first-born infants. About 85% of the mothers who gave birth to a macrosomic infant had a macrosomic infant in a subsequent pregnancy. CONCLUSIONS/INTERPRETATION: Although it is clear that glycaemic control contributes to birthweight in women with type 1 diabetes, the birthweight of an earlier born infant appears to be a much better predictor of the birthweight of a subsequent infant than HbA1c levels during pregnancy. It may, therefore, be used to identify patients at risk of giving birth to a macrosomic infant. Daily home monitoring of glucose levels, rather than HbA1c levels, should be used for assessment of maternal glycaemia during pregnancy.

[Diabetes and pregnancy; the prevention of hypoglycaemia]. / Diabetes en zwangerschap; het voorkómen van hypoglykemie.

In women with type-1 diabetes, the prevalence of maternal and fetal complications is high despite the overall adequate blood glucose control (HbA1c < 7%). Further improvements are hampered by the high incidence of maternal hypoglycaemia, including coma, especially during the first trimester of pregnancy. The reasons for this include the intensified insulin treatment, the decrease in hypoglycaemia awareness and the increase in glucose fluctuations. A further improvement of glucose control would provisionally seem possible only by using short-acting insulin analogues. These agents are currently under investigation. Continuous subcutaneous glucose measurements early in pregnancy show considerable glucose fluctuations despite almost normal HbA1c values. Moreover, they often reveal a hypoglycaemic event that the pregnant woman has not recognised. It is possible that these glucose fluctuations, rather than the too high average blood glucose levels, are responsible for congenital malformations and fetal macrosomia. Neonatal hypoglycaemia is associated with poor psychoneurological development. This relationship has not been established for maternal hypoglycaemia during pregnancy.

Effect of breast milk of diabetic mothers on bodyweight of the offspring in the first year of life.

OBJECTIVE: There is increasing evidence that in healthy populations, breast-fed infants are leaner than formula-fed infants. It is of interest to know the effects of breast-feeding on infant weight in case of maternal diabetes, given the high incidence of fetal macrosomia and risk of childhood obesity in this population. DESIGN AND SUBJECTS: As part of a nation-wide study in the Netherlands on diabetes and pregnancy, 229 women with Type 1 diabetes were sent a questionnaire on weight and height of their infant, the type of nutrition given during the first 6 weeks of life, the duration of lactation and intercurrent diseases during the first year of life. RESULTS AND CONCLUSION: Our data show no significant difference between breast-,formula-, and mixed-fed infants in weight and body mass index (BMI) at 1 y of age, which is not in accordance with the findings in nondiabetic populations.

Poor glucose control in women with type 1 diabetes mellitus and 'safe' hemoglobin A1c values in the first trimester of pregnancy.

OBJECTIVE: To observe glycemic excursions, measured continuously over 24 h, in relation to hemoglobin A1c values in the first trimester of pregnancy of women with type 1 diabetes mellitus. METHODS: The MiniMed Continuous Glucose Monitoring System (CGMS) was used to obtain glucose values every 5 min during 24 h. Hemoglobin A1c was determined at the end of the continuous glucose recording and 6-12 weeks after the continuous glucose recording. RESULTS: Continuous glucose recordings were obtained in 13 women between 7 and 15 weeks of gestation. Nine patients had hemoglobin A1c levels of < or = 7.0% (< 1% above the upper limit of normal range) while up to 41.3% of the readings had values of < 3.9 mmol/l (70 mg/dl) and up to 52.8% of the readings had values of > 7.8 mmol/l (140 mg/dl). CONCLUSIONS: Hemoglobin A1c does not reflect the complexities of glycemic control in women with type 1 diabetes who are considered to have accomplished tight glycemic control in the first trimester of pregnancy.