The association between vascular complications during pregnancy in women with Type 1 diabetes and congenital malformations.

AIMS: To assess the association between vascular complications of diabetes and the risk of congenital malformations in pregnant women with Type 1 diabetes.

METHODS: We conducted an observational retrospective cohort study in women with Type 1 diabetes who received care consecutively from three tertiary care diabetes-in-pregnancy clinics in Calgary, Alberta, Canada. Multivariable logistic regression was used to assess the association between vascular complications (retinopathy, nephropathy and pre-existing hypertension) and congenital malformations in offspring of women with Type 1 diabetes.

RESULTS: Of 232 women with Type 1 diabetes, 49 (21%) had at least one vascular complication and there were 52 babies with congenital malformations. Maternal age (31.8 ± 5.0 vs. 29.4 ± 4.7 years, P < 0.01), diabetes duration (20.9 ± 6.7 vs. 11.2 ± 7.4 years, P < 0.01) and pre-eclampsia rate (12.5% vs. 1.3%, P < 0.01) were higher in mothers with vascular complications than in those without. Multivariable analyses showed that vascular complications were not associated with an increased risk of congenital malformations (odds ratio 1.16, 95% confidence interval 0.46 to 2.88).

CONCLUSIONS: Vascular complications are common, occurring in one-fifth of pregnant women with Type 1 diabetes, and in this study do not appear to be associated with an increased risk of congenital malformations in children.