A new study suggests that pregnant women can significantly reduce their risk of developing hypertensive disorders of pregnancy by limiting sedentary time and increasing light physical activity. The research, presented at the American Heart Association’s EPI|Lifestyle Scientific Sessions 2026, found that women who sat for about eight hours a day and engaged in at least seven hours of light physical activity, along with about 22 minutes of higher-intensity activity and nine hours of sleep, had a 30% lower risk of developing conditions like gestational hypertension and preeclampsia.
“Our study suggests that in the real world, where daily routines vary widely, it may actually be the balance of sitting time and light intensity movement across the entire day that matters most,” said lead study author Kara Whitaker, Ph.D., M.P.H., FAHA, an associate professor at the University of Iowa. “This doesn’t mean exercise isn’t beneficial – rather, that when it comes to hypertensive disorders of pregnancy, everyday movement and limiting long periods of sitting may play a bigger role than we previously understood.”
The study included 470 pregnant women from three U.S. cities who wore monitors to track their activity and sleep across each trimester. About 18.6% of participants developed hypertensive disorders of pregnancy. The researchers found that sedentary behavior and light physical activity were the strongest predictors of risk. The optimal daily pattern included about six hours of sitting, nearly eight hours of light physical activity, four minutes of higher-intensity exercise, and roughly 10 hours of rest, which was linked to an 8% chance of developing hypertensive disorders – compared to 16.9% among women with a typical pattern.
“This line of research could give patients and clinicians more practical, achievable ways to support healthier pregnancies,” Whitaker said. The findings align with the American Heart Association’s Life Essential 8 for Pregnancy recommendations, which encourage moving throughout the day, adequate sleep, and healthy eating.
Natalie A. Bello, M.D., M.P.H., an American Heart Association volunteer expert who was not involved in the study, noted that while the association between physical activity and lower risk is promising, “it remains to be seen whether this association is causal, and future studies designed to increase physical activity and reduce sedentary behavior in pregnancy are needed.”
The study had limitations, including a predominantly white, higher-educated participant group, and the small number of hypertensive cases prevented separate analysis of preeclampsia and gestational hypertension. More research with diverse populations is needed to confirm the findings.
