Risk of complications of pregnancy in women with type 1 diabetes: nationwide prospective study in the Netherlands

Abstract

Objective To investigate maternal, perinatal, and neonatal outcomes of pregnancies in women with type 1 diabetes in the Netherlands. Design Nationwide prospective cohort study. Setting All 118 hospitals in the Netherlands. Participants 323 women with type 1 diabetes who became pregnant between 1 April 1999 and 1 April 2000. Main outcome measures Maternal, perinatal, and neonatal outcomes of pregnancy. Results 84% (n = 271) of the pregnancies were planned. Glycaemic control early in pregnancy was good in most women (HbA 1c ≤ 7.0% in 75% (n = 212) of the population), and folic acid supplementation was adequate in 70% (n = 226). 314 pregnancies that went beyond 24 weeks' gestation resulted in 324 infants. The rates of pre-eclampsia (40; 12.7%), preterm delivery (101; 32.2%), caesarean section (139; 44.3%), maternal mortality (2; 0.6%), congenital malformations (29; 8.8%), perinatal mortality (9; 2.8%), and macrosomia (146; 45.1%) were considerably higher than in the general population. Neonatal morbidity (one or more complications) was extremely high (260; 80.2%). The incidence of major congenital malformations was significantly lower in planned pregnancies than in unplanned pregnancies (4.2% (n = 11) v 12.2% (n = 6); relative risk 0.34, 95% confidence interval 0.13 to 0.88). Conclusion Despite a high frequency of planned pregnancies, resulting in overall good glycaemic control (early) in pregnancy and a high rate of adequate use of folic acid, maternal and perinatal complications were still increased in women with type 1 diabetes. Neonatal morbidity, especially hypoglycaemia, was also extremely high. Near optimal maternal glycaemic control (HbA 1c ≤ 7.0%) apparently is not good enough.

Anti-angiogenic factors and pre-eclampsia in type 1 diabetic women

“…Of these, 30 women developed pre-eclampsia and 108 were confirmed as being without pre-eclampsia. Thus 22% of the type 1 diabetic women with completed pregnancies and known outcome developed pre-eclampsia, an incidence consistent with previous reports [2][3][4][5]. Of the 30 pre-eclampsia cases, 28 were diagnosed after visit 3, while two were diagnosed at or before visit 3.…”

“…Pre-eclampsia, a major cause of premature delivery and maternal and fetal death [1], has a much higher incidence in women with type 1 diabetes mellitus than in the nondiabetic population (∼20% vs ∼5% respectively) [2][3][4][5]. The underlying mechanisms for the increased risk of pre-eclampsia in women with diabetes are unknown and predictive measures for its early detection are lacking.…”

Prevention of neural tube defects by loss of function of inducible nitric oxide synthase in fetuses of a mouse model of streptozotocin-induced diabetes

“…The incidence of congenital malformation in type 1 diabetic pregnancy is estimated to be 4.2% to 9.4% compared with approximately 1% in the general population [1][2][3]. Although a planned pregnancy with optimal blood glucose control and folic acid supplements at the time of conception reduces the risk of congenital malformations, a recent prospective study showed that the incidence of congenital malformations is still elevated in women with type 1 diabetes [4]. The congenital malformations associated with diabetic pregnancy affect many major organs, including the central nervous, cardiovascular, gastrointestinal, urogenital and musculoskeletal systems [5,6].…”

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

“…Macrosomia is a frequent complication in pregnancies of women with type 1 diabetes [1][2][3][4]. Macrosomia may lead to short-term complications such as increased rates of Caesarean section, shoulder dystocia and neonatal hypoglycaemia [5][6][7][8][9][10].…”