While preeclampsia and stroke during pregnancy are far more common in Black women in the United States, almost all study of links between these two conditions has been done on white women.
In a new study, researchers worked to better understand the risks.
This included examining 25 years of data involving 59,000 participants in the Black Women's Health Study.
The researchers found that Black women with a history of hypertensive disorders of pregnancy (HDOP) had about a 66% heightened long-term risk of stroke.
"Our findings could provide a partial explanation for the disproportionately high occurrence of stroke among Black women compared to other populations," said author Dr. Shanshan Sheehy, an assistant professor of medicine from Boston University Chobanian & Avedisian School of Medicine.
Preeclampsia is a dangerous complication of late pregnancy marked by high blood pressure. Eclampsia is a severe condition that can follow, resulting in seizures.
Preeclampsia affects between 2% and 8% of pregnancies. Among U.S. Black women, the rate of preeclampsia and eclampsia is 60% higher than in white women.
That is seen in numbers of the two conditions, with 70 cases per 1,000 deliveries reported for Black women in 2014 compared to 43 per 1,000 deliveries for white women.
Researchers said there has also been a concerning rise in severe preeclampsia rates among Black women in recent years.
The American Heart Association (AHA) recently updated its guidelines to include pregnancy complications as risk factors for stroke. The AHA has emphasized the importance of further studies on the risk of stroke in women, including those from underrepresented populations.
This study included nearly 43,000 women who had previously given birth and had no preexisting heart disease at the outset. Questionnaires every two years gathered information on preeclampsia, gestational high blood pressure and stroke. Neurologists also reviewed medical records for women who reported having had a stroke.
Between 1995 and 2019, 1,555 strokes were reported, with 310 of them in women with a history of HDOP.
Women with a previous occurrence of HDOP were estimated to have a 66% higher risk of stroke compared to mothers who did not experience those pregnancy complications. For women with a history of preeclampsia, the estimated risk was 53% higher.
This link was seen in both women under age 60 and in older women. It was also seen in women who had a healthy weight during early adulthood and in those who were overweight or obese during that time.
"Our research offers evidence that a woman's pregnancy history can be a crucial factor in assessing and preventing long-term stroke risk,"Sheehy said in a university news release.
She emphasized the importance of considering HDOP when developing heart screening recommendations, especially for Black women. With this, health care providers could better tailor preventive measures and gauge risk.
Study findings were published July 6 in the journal NEJM Evidence.
More information
The American Stroke Association has more on Black Americans and stroke.
SOURCE: Boston University Chobanian & Avedisian School of Medicine, news release, July 6, 2023
