A study of nearly 500 pregnant women across three U.S. states found that limiting daily sedentary time to about eight hours and engaging in at least seven hours of light physical activity, alongside moderate higher-intensity activity and adequate sleep, was associated with a 30% lower risk of developing hypertensive disorders like gestational hypertension or preeclampsia. The research, presented at the American Heart Association's EPI|Lifestyle Scientific Sessions 2026, indicates that the balance of sitting and light movement throughout the day may be more critical for blood pressure management during pregnancy than previously understood.
Lead researcher Kara Whitaker, Ph.D., M.P.H., FAHA, from the University of Iowa, noted that while exercise remains beneficial, everyday movement and reducing prolonged sitting could play a significant role in preventing pregnancy-related hypertension. High blood pressure affects 5%-10% of pregnancies and is a leading cause of maternal and fetal morbidity and mortality. The study's findings align with the American Heart Association’s Life Essential 8 for Pregnancy recommendations, which encourage movement, healthy eating, and blood pressure monitoring.
Participants wore activity monitors for seven consecutive days during each trimester. The optimal daily pattern linked to the lowest risk—about 8% chance of hypertensive disorders versus 16.9% in typical patterns—included six hours of sitting, eight hours of light activity, four minutes of higher-intensity activity, and ten hours of rest. Risk increased significantly when sitting exceeded ten hours daily or light activity fell below five hours. Natalie A. Bello, M.D., M.P.H., an American Heart Association volunteer expert, emphasized that while the study shows incremental associations between more activity and lower risk, causal links require further investigation through trials designed to increase activity and reduce sedentary behavior in pregnancy.
The study had limitations, including a predominantly white, higher-educated participant group, meaning results may not generalize to other populations. Additionally, the relatively small number of hypertension cases prevented separate analysis of preeclampsia and gestational hypertension, which may have different relationships with activity. Researchers call for larger, more diverse studies to confirm findings and refine guidelines. Whitaker highlighted that current pregnancy guidelines lack clear quantitative targets for sitting and light activity, and this research could help shape future recommendations, offering practical strategies for healthier pregnancies and potentially reducing long-term cardiovascular risks for women.
