Haemorrhage risk of brain arteriovenous malformation during pregnancy and puerperium

Background This study aimed to assess whether pregnancy and puerperium were associated with the risk of brain arteriovenous malformation (bAVM) haemorrhage. Methods A retrospective review was conducted in Xiangya Hospital, Central South University from January 2012 to December 2021. A case–crossover design was adopted to calculate the incidence density of bAVM-related haemorrhage among female patients in risk (pregnancy and puerperium) and control (non-pregnancy and non-puerperium) periods, according to four scenarios observed in different populations (scenario I: patients with haemorrhagic bAVM of all ages; scenario II: patients with haemorrhagic bAVM of all ages, with at least one previous pregnancy; scenario III: patients with haemorrhagic bAVM who are of reproductive age (15–45 years); scenario IV: patients with haemorrhagic bAVM of reproductive age (15–45 years), with at least one previous pregnancy. Next, a comprehensive literature aggregation (up to April 2022) was performed for evidence synthesis. Results Among the 311 female patients with haemorrhagic bAVM, a significant haemorrhage risk during pregnancy and puerperium was found in Scenarios I (relative risk [RR], 2.08; 95% CI, 1.28 to 3.39), II (RR, 3.21; 95% CI, 1.95 to 5.31) and IV (RR, 2.92; 95% CI, 1.73 to 4.93); however, a suggestive risk was found in scenario III (RR, 1.62; 95% CI, 0.99 to 2.67). Evidence synthesis revealed a consistent haemorrhage risk among patients of all ages (RR, 3.15; 95% CI, 1.93 to 5.15) and those of reproductive age (RR, 1.29; 95% CI, 0.89 to 1.86). Conclusion Compared with most previous studies, a higher but relatively moderate risk for bAVM-related haemorrhage was identified during pregnancy and puerperium. Individualised prevention and treatment strategies should be preferred when neurosurgeons make clinical decisions.