Preterm delivery in normoalbuminuric, diabetic women without preeclampsia: the role of metabolic control

OBJECTIVE: The aim of this study was to examine the importance of glycemic regulation on the risk of preterm delivery in women with normoalbuminuria and no preeclampsia later in pregnancy. STUDY DESIGN AND METHODS: A prospective study of 71 women with type 1 diabetes mellitus where complete data were collected on HbA1c, insulin dose, and albumin excretion rate from week 12 and every second week hereafter. Fundus photography was performed and diurnal blood pressure measured three times during pregnancy. RESULTS: The preterm rate was 23% and women delivering preterm showed higher HbA1c throughout pregnancy. At regression analysis HbA1c was the strongest predictor for preterm delivery from week 6 to 32, also when including insulin dose, BMI, age, duration of diabetes, and diurnal blood pressure. The risk of delivering preterm was more than 40% when HbA1c was above 7.7% in week 8. Diurnal blood pressure was not found associated with preterm delivery. CONCLUSION: The quality of glycemic regulation in the early and mid-pregnancy is a major, independent risk factor for preterm delivery in normoalbuminuric diabetic women without preeclampsia.