During pregnancy, women can reduce their risk of developing hypertensive diseases by almost 30% by limiting their sitting time to no more than 8 hours a day and increasing their light daily physical activity to at least 7 hours a day, according to a preliminary study presented at the American Heart Association’s EPI|Lifestyle Science Session 2026. The conference will be held in Boston from March 17-20, 2026, and will provide the latest science in population-based health, epidemiology, prevention, lifestyle, and wellness. cardiometabolic health.
“Our study suggests that in the real world, where daily life is very different, what really matters most may be the balance between sitting time and light intensity movement throughout the day,” said study lead author Kara Whitaker, Ph.D., MPH, FAHA, associate professor in the Department of Health, Sports, and Human Physiology at the University of Iowa in Iowa City, Iowa. “This does not mean that exercise is not beneficial; rather, restrictions on daily movement and prolonged sitting may play a larger role when it comes to pregnancy-induced hypertension than previously understood.”
According to the American Heart Association, high blood pressure during pregnancy and other adverse pregnancy conditions are associated with an increased risk of cardiovascular disease later in life. Physical activity and sleep patterns are associated with the risk of cardiovascular disease, but how 24-hour activity patterns affect the risk of hypertension during pregnancy is less well-studied.
Hypertension occurs in up to 5% to 10% of all pregnancies and is a major cause of fetal and maternal morbidity and mortality. This study aimed to identify optimal 24-hour behavior and activity patterns across the trimesters of pregnancy that minimize the risk of gestational hypertension.
The research results revealed the following:
- Of the 470 study participants, 18.6% of women developed gestational hypertension (gestational hypertension or preeclampsia).
- Sedentary behavior and light physical activity were the strongest predictors of pregnancy risk for hypertensive diseases across all trimesters of pregnancy.
- The lowest-risk daily activity pattern included about 6 hours of sitting, almost 8 hours of light physical activity, 4 minutes of more intense activity (traditional exercise), and about 10 hours of rest. This daily pattern had an 8% chance of gestational hypertension compared with 16.9% for those with the typical daily pattern.
- Compared to a typical daily exercise pattern, an optimal combination of activities reduced the risk of hypertension-related diseases in pregnant women by more than half. When compared to the least healthy daily movement patterns measured in this study, the optimal activity combination reduced risk by nearly 80%.
- The risk of gestational hypertension increased for those who sat for more than 10 hours per day or had less than 5 hours of light activity per day.
- These findings highlight that sedentary time and light physical activity are important modifiable behaviors that may help prevent the development of gestational hypertension, which in turn may have important effects on women’s lifelong heart health.
“Both sedentary behavior and high blood pressure are becoming increasingly common during pregnancy, and we know that physical activity is associated with lower blood pressure in non-pregnant people,” said Natalie A. Bello, MD, MPH, a volunteer expert with the American Heart Association and a member of the writing group for the AHA’s scientific statement Prevention and Treatment of Maternal Stroke During Pregnancy and Postpartum and Guidelines for the Prevention, Detection, Evaluation, and Management of Hypertension in Adults. “Researchers extended this to a pregnant population, with approximately 20% of participants developing gestational hypertension. They found a progressive association between more physical activity and a lower risk of developing pre-eclampsia and gestational hypertension. It is not yet clear whether this association is causal, and it is important to note that increasing the amount of physical activity during pregnancy and reducing sedentary behavior. “Future research aimed at reducing this is needed.” Bello, who was not involved in the study, is an associate professor of cardiology at the Smit Heart Institute at Cedars-Sinai Medical Center and director of women’s cardiovascular health and cardiology at Atria Health and Research Institute in Los Angeles.
The findings are consistent with the American Heart Association’s 8 Life Essentials for Pregnancy recommendations, which encourage women to find ways to be physically active throughout the day, get enough sleep, eat healthy foods, manage cholesterol and blood sugar levels, and monitor blood pressure.
“These findings have the potential to change the way we think about physical activity and sleep during pregnancy,” Professor Whittaker said. “Currently, there are no clear, quantitative guidelines for how much sitting or light exercise is healthiest during pregnancy, and our results provide early evidence that may help shape those recommendations in the future. Ultimately, this line of research may provide patients and clinicians with more practical and achievable ways to support healthier pregnancies.”
Research details, background and design:
- The study involved 470 women between the ages of 18 and 45. 83% self-reported being non-Hispanic white. Participants were enrolled in the study from 2021 to 2024 at three medical centers in Iowa, Pennsylvania, and West Virginia.
- All women were in their first trimester (before 13 weeks’ gestation) at enrollment and were followed up to 6 weeks postpartum.
- Each study participant wore two monitors 24 hours a day, seven consecutive days during each trimester of pregnancy to measure sedentary behavior, sleep, and 24-hour activity cycles (sedentary behavior, physical activity, and sleep composition). This data was analyzed along with health records related to hypertensive disorders and other adverse pregnancy outcomes.
- Activity was measured using a small wearable monitor that tracked time spent lying down, sitting, standing, and walking. The clock assessed participants’ sleep duration.
- The incidence of gestational hypertension and preeclampsia was recorded from the medical records of study participants, and using a statistical model, the risk of hypertensive diseases during pregnancy was predicted based on 24-hour exercise behavior data and calculated for each gestational period.
This study has some limitations, as study participants were mostly white and tended to be more educated and have higher income levels, so the results may not reflect the experiences of people in other population groups. Additionally, because the number of gestational hypertension cases was relatively small, the researchers were unable to analyze the incidence of preeclampsia and gestational hypertension separately, and these two conditions may have different relationships with physical activity. The authors note that studies with larger numbers of participants and people from other population groups are needed to confirm the results and better understand how specific physical activity patterns correlate with different pregnancy hypertension syndromes.
sauce:
american heart association
