Introduction: Type 1 diabetes has wide-ranging effects for expectant mothers and their unborn children. Optimal blood sugar control minimizes complications for both. We assessed maternal and neonatal outcome in relation to glycemic control.
Material and methods: Retrospective evaluation of pregnancies among type 1 diabetic women in Iceland during 1999-2010, with information collected from maternity and newborn records on disease severity, HbA1c values before and during pregnancy, delivery mode and complications.
Results: There were 93 pregnancies among 68 women (47% primigravid). Mean age was 29 years and mean time from diabetes diagnosis 16 years (median 19, range <1-35 years). Retinal changes affected 57%, chronic hypertension and thyroid disease 13%, kidney disease and neuropathy <10%. Mean HbA1c before pregnancy was 7.8% declining to 7.5% in first and 6.3% by third trimester. Women <25 had worse first trimester blood sugar control compared to those 25-35 (p<0.04) and >35 years (p=0.02). Delivery was induced in 40% and the cesarean section rate was 65%. Mean gestation was 37+2 weeks. There were two stillbirths. Preterm deliveries were 28%. Congenital anomalies affected 9% of newborns (mostly cardiac). One-third of newborns developed diabetic fetopathy, one-quarter jaundice, both associated with worse maternal bloodsugars.
Conclusions: Most women with type 1 diabetes improved blood sugar control during pregnancy, which became good or acceptable by the last trimester by HbA1c values. Cesarean section was over three times more frequent than in the general population. Neonatal complications and congenital anomalies were also more common. To minimize complications improved control of bloodsugar is needed before and throughout pregnancy.