Pregnant women with blood pressure disorders should be closely monitored after delivery, based on a Canadian study that found women with conditions like preeclampsia face increased stroke risk, even after leaving the hospital.
Published in the American Heart Association journal Stroke, this study looked at stroke risk among pregnant women in Canada between 2003 and 2016. The goal was to see how common stroke is among women within six weeks after delivery and to identify factors that impact risk for heart events.
In total, the study included data from more than 3.9 million deliveries during the 13-year study period. Data was obtained from a national registry called the Canadian Institute of Health Information, which tracks all hospitalizations in the Canadian health care system.
The good news, according to authors, is that overall risk of stroke following delivery was low. Among the 3.9 million deliveries included in the study, there were only 524 stroke cases that occurred during pregnancy or within six weeks of delivery. This translated to an overall rate of 13.4 strokes per 100,000 deliveries, about 7% of which were fatal.
Authors note that most cases were hemorrhagic strokes, which are caused by bleeding inside the brain, with just over half occurring post-delivery.
However, researchers also found that risk for stroke differed greatly based on women’s overall health. For example, women who were 40 years or older had 70% greater risk of stroke than those who were younger. Women with postpartum complications like bleeding or thrombophilia, which increases risk for blood clots, were also four times as likely to experience stroke than those without.
But by far, women with the greatest risk for stroke were those with high blood pressure disorders and existing heart conditions. Women with preeclampsia, which occurs when high blood pressure develops in the second half of pregnancy, had seven times greater risk for stroke than those without this condition. Worse, women with a more severe form of this condition, called eclampsia, were 66 times as likely to experience stroke compared to those without.
Women with congenital heart disease also faced 38 times greater risk for stroke than women without this condition.
The take-home message, according to authors, is that women with these risk factors should be closely monitored to help reduce risk of stroke and complications. Monitoring should also continue in the months after delivery, as most strokes appear to occur postpartum.
Experts hope that continued monitoring and treatment will help reduce risk for complications and help improve outcomes in pregnant women.