Incidence and causes of strokes associated with pregnancy and puerperium. A study in public hospitals of Ile de France. Stroke in Pregnancy Study Group.

BACKGROUND AND PURPOSE

The incidence, causes, and prognosis of nonhemorrhagic strokes and intraparenchymal hemorrhages occurring in association with pregnancy or puerperium are poorly understood.

METHODS

We carried out a retrospective (1989 through 1991) and prospective (1992) study in 63 public maternities (348,295 deliveries) of the region of Ile de France (10,660,554 inhabitants) and in the neurology, neurosurgery, and intensive care units of the same geographic area. Records of women who suffered a cerebrovascular event during pregnancy or the first 2 weeks postpartum were reviewed by two study neurologists. Stroke was defined according to the criteria of the World Health Organization.

RESULTS

Thirty-one cases of strokes were identified, including 15 nonhemorrhagic strokes (including strokelike deficits associated with eclampsia) and 16 intraparenchymal hemorrhages, assessed in all cases by CT scan and/or MRI. The incidence of nonhemorrhagic strokes in women who delivered in public maternities of Ile de France was 4.3 per 100,000 deliveries (95% confidence interval, 2.4 to 7.1) and that of intraparenchymal hemorrhage was 4.6 per 100,000 deliveries (95% confidence interval, 2.6 to 7.5). Eclampsia accounted for 47% of cases of nonhemorrhagic strokes. The other causes were extracranial vertebral artery dissection, postpartum cerebral angiopathy, inherited protein S deficiency, and disseminated intravascular coagulation associated with amniotic fluid embolism. The cause remained undetermined in four cases despite extensive investigations. Eclampsia accounted for 44% of intraparenchymal hemorrhages. Another 37% were due to rupture of a vascular malformation. The cause remained undetermined in three cases. There were four maternal deaths (all associated with intraparenchymal hemorrhage), three of them in eclamptic women. Fetal mortality and prematurity were associated with eclampsia.

CONCLUSIONS

The incidence of nonhemorrhagic stroke does not seem to be much increased during pregnancy and early puerperium. In contrast to that in the nonpregnant state, the frequency of intraparenchymal hemorrhage in pregnancy appears to be similar to that of nonhemorrhagic strokes, suggesting that pregnancy may increase the risk of cerebral hemorrhage. Eclampsia is the main cause of both nonhemorrhagic stroke and intraparenchymal hemorrhage. Intraparenchymal hemorrhage associated with eclampsia carries a poor prognosis.