Influence of Pregnancy on Hemorrhage Risk in Women With Cerebral and Spinal Cavernous Malformations

Background and Purpose: Pregnancy as a hemorrhage risk factor in women with cavernous malformations (CMs) is controversial. We describe prospective hemorrhage risk in women who become pregnant after an established CM diagnosis. Methods: Beginning in 2015, we recruited consecutive patients with radiologically confirmed CM of the brain or spinal cord to participate in a prospective registry. Participants underwent a baseline and annual medical record review, imaging review, and annual surveys to ascertain pregnancies, deliveries, and neurological complications. We collected prospective hemorrhage data on reproductive age women. We calculated prospective hemorrhage rates on childbearing age patients based on the number of hemorrhages occurring post-CM diagnosis during pregnancy and nonpregnancy, divided by the years of follow-up and censored at last follow-up, age 46, or surgery in sporadic-form CM. The hemorrhage rates were compared and the 95% CI presented with a P value of <0.05. Results: Of 160 women, 90 presented with CM under the age of 46 (average age 31.6 years; 25.6% familial form; 46.7% with hemorrhage; 24.4% brain stem location). These 90 patients had 136 pregnancies before CM diagnosis; 36 pregnancies occurred at or after the diagnosis of CM. Four patients had a hemorrhage while pregnant or postpartum leading to the first CM diagnosis. During 402.6 years of follow-up while not pregnant, 42 hemorrhages occurred prospectively yielding a 10.4% per year (95% CI, 7.5-14.0) risk of hemorrhage while not pregnant. No hemorrhages occurred during 32 prospective pregnancies (26 live births including 1 twinset and 7 nonviable fetuses) after CM diagnosis during 26.9 years of pregnancy time yielding a rate of 0% per year (95% CI, 0-13.6). We found no statistical difference in the rates of hemorrhage during pregnant and nonpregnant time (P=0.09). No hemorrhage occurred during delivery. Conclusions: Our prospective data suggest that pregnancy does not increase the risk of hemorrhage in women with a known brain or spinal cord CM and that vaginal delivery is safe in appropriate candidates.