Study Links Reduced Sitting Time and Increased Light Activity to Lower Pregnancy Hypertension Risk

Pregnant women may reduce their risk of developing hypertensive disorders by nearly 30% by limiting sedentary time to no more than eight hours daily and increasing light physical activity to at least seven hours daily, according to preliminary research presented at the American Heart Association's EPI|Lifestyle Scientific Sessions 2026. The study of 470 pregnant women across three U.S. cities found that sedentary behaviors and light physical activity were the strongest predictors of hypertensive disorder risk across all trimesters, with optimal activity patterns reducing risk by more than half compared to typical patterns.

The research measured 24-hour activity patterns during each trimester using wearable monitors, finding that women who maintained about six hours of sitting, nearly eight hours of light physical activity, four minutes of higher-intensity activity, and roughly ten hours of rest daily had an 8% chance of developing hypertensive disorders compared to 16.9% among those with typical patterns. Risk increased significantly for women who sat more than ten hours daily or engaged in less than five hours of light activity. These findings align with the American Heart Association's Life Essential 8 for Pregnancy recommendations, which encourage movement throughout the day alongside other health measures.

Lead researcher Kara Whitaker noted that while exercise remains beneficial, everyday movement and limiting prolonged sitting may play a larger role in preventing pregnancy hypertension than previously understood. The study's results could help shape future quantitative guidelines for pregnancy activity, as current recommendations lack clear benchmarks for sitting and light movement. According to the American Heart Association, high blood pressure during pregnancy affects 5%-10% of pregnancies and is a leading cause of maternal and fetal complications, with adverse pregnancy outcomes linked to increased future cardiovascular disease risk.

Study limitations include a predominantly white participant group with higher education and income levels, potentially limiting generalizability, and insufficient cases to separately analyze preeclampsia and gestational hypertension. The research abstract, not yet peer-reviewed, calls for future studies to test whether interventions reducing sedentary time and increasing movement can causally lower hypertension risk. Additional resources on pregnancy and cardiovascular health are available through the American Heart Association's scientific statements, including their guidance on Sedentary Behavior and Light-Intensity Physical Activity During Pregnancy and Cardiovascular Health.