Objective
To examine fetal malformations in mother–infant pairs with and without pregnancy-related hypertension.
Methods
This was an observational, population-based study of women delivering a singleton at our hospital. Specific fetal malformations identified in women with gestational hypertension or preeclampsia were compared to those without pregnancy-related hypertension. Women with chronic hypertension, superimposed preeclampsia on chronic hypertension and pregestational diabetes were excluded.
Results
Between March 2002 and December 2012, a total of 151 997 women delivered, and 10 492 (7%) had preeclampsia, 4282 (3%) had gestational hypertension and 137 223 (90%) were referent normotensive controls. Women with preeclampsia were significantly more likely to deliver infants with malformations when compared to normotensive controls (2.5% versus 1.6%, p < 0.001), whereas women with gestational hypertension were not (1.9% versus 1.6%, p = 0.16). The overall risk for fetal malformation associated with preeclampsia remained significant following logistic regression for age, race, parity and maternal body-habitus (adjusted OR 1.5; 95% CI: 1.3–1.7). Only single-organ system malformations – microcephaly and hypospadias – remained associated with preeclampsia (p < 0.001), and fetal growth restriction was a co-factor for both.
Conclusions
Preeclampsia was associated with increased rates of fetal malformations when compared to normotensive women – specifically microcephaly and hypospadias. These associations appear predominantly as a consequence of impaired fetal growth.