Rupture Risk of Cerebral Arteriovenous Malformations During Pregnancy and Puerperium: A Single-Center Experience and Pooled Data Analysis

Objective: Whether rupture risk of cerebral arteriovenous malformation (AVM) is higher during pregnancy and puerperium remains controversial. This study aimed to compare risk of rupture in pregnant and nonpregnant female patients with AVM in a singer-center series and assess current evidence regarding rupture risk of AVM during pregnancy and puerperium by pooled data analysis. Methods: We retrospectively reviewed female patients with AVM in our center from January 2006 to August 2017. Hemorrhage events and patient-years were calculated during exposure period and nonexposure period, which was defined as either the interval from birth until AVM obliteration or last follow-up after subtracting the exposure period. Poisson rate ratio analysis was used to compare hemorrhage rate between the 2 periods. Pooled data analysis was performed by up-to-date literature review via PubMed and EMBASE databases. Results: In 264 female patients with AVM, overall annual hemorrhage rate for 222 total hemorrhages during an average of 7484 patient-years was 2.97%. Eight hemorrhages occurred in exposure periods, 214 hemorrhages occurred in nonexposure periods, and 155 hemorrhages occurred in nonexposure periods of reproductive-age patients, translating to annual hemorrhage rates of 5.40% in exposure periods, 2.92% in nonexposure periods, and 3.82% in nonexposure periods of reproductive-age patients. Pooled data analysis showed a higher annual hemorrhage rate in exposure periods than in nonexposure periods (5.59% vs. 2.52%; 95% confidence interval 1.52-6.70, P = 0.002). Conclusions: This study demonstrated an increase in annual rate of cerebral AVM hemorrhage during pregnancy and puerperium. Female reproductive-age patients with cerebral AVM may have higher risks of AVM rupture. Further evaluation by well-designed prospective or randomized cohort studies is needed.