Cerebral white matter lesions after pre-eclampsia

Women who have had pre-eclampsia in their previous pregnancies demonstrate a greater prevalence of cerebral white matter lesions several years after the pregnancy than women who have been normotensive during their pregnancy. Both the pathophysiology and the timing of development of these lesions are uncertain. White matter lesions, in the general population, are associated with an increased risk of stroke, dementia and death.

The objective of the study was to determine the prevalence of cerebral white matter lesions amongst women with severe pre-eclampsia at delivery, 6months and 1year postpartum and to establish the possible pathophysiology and risks factors.

This was a longitudinal study performed at Steve Biko Academic Hospital, a tertiary referral hospital in Pretoria South Africa. Ninety-four women with severe pre-eclampsia were identified and recruited during the delivery admission. Magnetic resonance imaging (MRI) of the brain was performed post - delivery and at 6months and 1year postpartum.

Cerebral white matter lesions were demonstrated in 61.7% of women at delivery, 56.4% at 6months and 47.9% at 1year. Majority of the lesions were found in the frontal lobes of the brain. The presence of lesions at 1year post-delivery was associated with the number of drugs needed to control blood pressure during pregnancy (OR 5.1, 95% CI 2.3-11.3, p<0.001). The prevalence of WMLs at 1year was double in women with chronic hypertension at 1year compared to those women who were normotensive (65.1% vs 32.3%).

Women who require 2 or more drugs to control blood pressure during pregnancy have an increased risk of developing cerebral white matter lesions after delivery.