(HealthDay) -- Pregnant women are at higher risk of bleeding in the brain from vessel abnormalities known as arteriovenous malformations, a new study indicates.
Arteriovenous malformations are tangled bits of veins and arteries that can affect circulation, according to the U.S. National Library of Medicine.
Ruptured arteriovenous malformations can lead to death or serious disability, the researchers noted.
In conducting the study, Dr. Bradley Gross and Rose Du, from Harvard Medical School, reviewed information on 54 women with confirmed arteriovenous malformations between 2002 and 2010. They calculated the women's overall risk of bleeding, as well as their risk of bleeding during a total of 62 pregnancies. The study revealed four of the women had a total of five bleeding events while they were pregnant.
As a result, the researchers concluded that women with arteriovenous malformations had an 8 percent risk of rupture and bleeding during pregnancy. In contrast, the rate of bleeding while the women were not pregnant was about 1 percent per year, according to the report published in the August issue of Neurosurgery.
In following the women to the age of 40, the investigators found the risk of bleeding during pregnancy increased. At this point, it was 18 times higher than when the women were not pregnant.
The study authors noted that in the four cases of bleeding events during pregnancy, the arteriovenous malformations caused sudden headache and other symptoms between 22 and 39 weeks of pregnancy. Prompt treatment, however, saved the lives of the women and their babies, they pointed out in a journal news release.
The researchers advised that all women with arteriovenous malformations who plan to have children be treated. If an arteriovenous malformation is discovered during pregnancy, women should be counseled on the risks of treatment versus careful monitoring during the pregnancy. They also recommended that women with the malformation have a cesarean-section delivery.
More information: Abstract