A study of nearly 500 pregnant women across three U.S. cities found that limiting sedentary time and increasing light physical activity significantly reduces the risk of developing hypertensive disorders during pregnancy. The research, presented at the American Heart Association's EPI|Lifestyle Scientific Sessions 2026, indicates women who maintained about eight hours of sitting, at least seven hours of light activity, 22 minutes of higher-intensity activity, and nine hours of sleep daily had a 30% lower risk.
Lead study author Kara Whitaker, Ph.D., M.P.H., FAHA, noted 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." The findings suggest everyday movement and limiting prolonged sitting may play a more significant role in preventing pregnancy-related hypertension than previously understood, though exercise remains beneficial.
Hypertensive disorders affect 5%-10% of pregnancies and are leading causes of maternal and fetal complications. The study measured 24-hour activity patterns across trimesters using wearable monitors. Results showed sedentary behaviors and light physical activity were the strongest predictors of risk. The optimal daily pattern included six hours of sitting, eight hours of light activity, four minutes of higher-intensity activity, and ten hours of rest, linked to an 8% chance of hypertensive disorders versus 16.9% with typical patterns.
Risk increased for women sitting more than ten hours daily or engaging in less than five hours of light activity. Compared to typical patterns, the optimal activity combination reduced risk by over half, and by nearly 80% compared to the least healthy patterns. These findings align with the American Heart Association's Life Essential 8 for Pregnancy recommendations, which encourage movement throughout the day.
Natalie A. Bello, M.D., M.P.H., an American Heart Association volunteer expert, emphasized that "both sedentary behavior and hypertension in pregnancy are increasingly common" and noted the study extends known physical activity benefits to pregnant populations. However, she cautioned that causal relationships require further investigation through studies designed to increase activity and reduce sedentary behavior during pregnancy.
The study's implications extend beyond pregnancy, as high blood pressure during pregnancy is associated with increased future cardiovascular disease risk. Whitaker explained these findings "have the potential to shift how we think about physical activity and sleep during pregnancy" and could help shape future quantitative guidelines for sitting and light movement. Currently, no clear guidelines exist for these specific behaviors during pregnancy.
Study limitations include a predominantly white, higher-education participant group, potentially limiting generalizability. The relatively small number of hypertensive disorder cases prevented separate analysis of preeclampsia and gestational hypertension, which may have different activity relationships. Researchers note more diverse studies are needed to confirm findings and understand specific pattern correlations.
For business and technology leaders, this research highlights growing intersections between health monitoring technology, preventive healthcare, and workforce wellness. Wearable devices that track activity patterns, like those used in the study, represent expanding markets in health technology. Employers in technology-driven industries might consider how such insights could inform workplace wellness programs, particularly for employees during life stages like pregnancy.
The study underscores the importance of practical, achievable health interventions that could reduce healthcare costs and improve outcomes. As Whitaker noted, this research could "give patients and clinicians more practical, achievable ways to support healthier pregnancies," potentially influencing both clinical practice and health technology development focused on preventive care.
