A new study presented at the American Heart Association's EPI|Lifestyle Scientific Sessions 2026 indicates that pregnant women may significantly reduce their risk of developing hypertensive disorders by modifying their daily activity patterns. The research, which followed 470 women across three U.S. cities from 2020-2025, found that limiting sedentary time to about eight hours daily while engaging in at least seven hours of light physical activity was associated with a 30% lower risk of conditions like gestational hypertension and preeclampsia.
Lead study author Kara Whitaker, Ph.D., M.P.H., FAHA, from the University of Iowa, explained that the balance between sitting time and light intensity movement throughout the day appears to be crucial. "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," Whitaker said. The study measured 24-hour activity patterns across all three trimesters using wearable monitors, providing comprehensive data on how daily behaviors impact pregnancy outcomes.
The findings revealed that sedentary behaviors and light physical activity were the strongest predictors of hypertensive disorder risk throughout pregnancy. Women who followed the optimal daily pattern—approximately six hours of sitting, nearly eight hours of light activity, four minutes of higher-intensity exercise, and about ten hours of rest—had an 8% chance of developing hypertensive disorders, compared to 16.9% among those with typical movement patterns. This represents a risk reduction of more than half compared to typical patterns and nearly 80% compared to the least healthy patterns measured in the study.
According to the American Heart Association, high blood pressure develops in 5%-10% of all pregnancies and is the leading cause of fetal and maternal disease and death. Natalie A. Bello, M.D., M.P.H., an American Heart Association volunteer expert not involved with the study, noted that "both sedentary behavior and hypertension in pregnancy are increasingly common, and in non-pregnant individuals we know that physical activity is associated with reductions in blood pressure." The study extends this understanding to pregnant populations, where nearly 20% of participants developed hypertensive disorders.
The research aligns with the American Heart Association's Life Essential 8 for Pregnancy recommendations, which encourage women to find ways to move throughout the day while also focusing on sleep, nutrition, and blood pressure management. These findings could influence future clinical guidelines, as there are currently no clear, quantitative recommendations for sitting or light activity during pregnancy.
Study limitations include the predominantly white participant demographic with higher education and income levels, which may limit generalizability to other populations. Additionally, the relatively small number of hypertensive disorder cases prevented separate analysis of preeclampsia and gestational hypertension, conditions that may have different relationships with physical activity. The researchers emphasize that more studies are needed to confirm these findings and better understand how specific activity patterns correlate with different hypertensive disorders.
The implications of this research extend beyond pregnancy outcomes. Since hypertensive disorders during pregnancy are associated with increased future cardiovascular disease risk, modifying daily activity patterns could have lifelong benefits for women's heart health. As Whitaker noted, "Ultimately, this line of research could give patients and clinicians more practical, achievable ways to support healthier pregnancies." The study was presented as preliminary research and will require peer-reviewed publication for full scientific validation.
