ABSTRACT
Incidence of AVM Rupture and Its Outcome in Women Who Are Not Pregnant Contemporary population-based studies show that the annual incidence of first-ever haemorrhage from an AVM is *0.5 per 100,000 adults (including pregnant women) (28,29). Studies at tertiary referral centres found the risk of haemorrhage from a known, unruptured AVM to be between 1% and 8% per year, and re-bleed rates between 5% and 34% per year; the risk of rebleed is greater for AVMs with exclusive deep venous drainage or deep brain location (30,31). The 30-day case-fatality after AVM haemorrhage was 18% (95% CI, 4-43%) in a population-based study of cases between 1965 and 1992 (32), but was lower (11%; 95% CI, 6-19%) in a contemporary population-based study (33).
Incidence of Rupture and Its Outcome During Pregnancy or the Puerperium Various studies have attempted to establish whether particular trimesters of pregnancy or mode of delivery influence the incidence of AVM rupture. Unfortunately, none of these studies is prospective or population based, and bias most probably plays a role. In particular, the occurrence of haemorrhage may discourage some women from becoming pregnant again, or may even be fatal, so preventing future pregnancies.
