Effect of daily physical activity on ambulatory blood pressure in pregnant women with chronic hypertension: A prospective cohort study protocol.

backgroundPhysical activity, a first-line approach for the treatment of non-gestational hypertension globally, has been shown to benefit most pregnant women in many respects. The benefits and risks of prenatal physical activity in complicated pregnancies, such as preeclampsia and chronic hypertension, require further investigation. It is worth conducting studies to address questions about physical activity during pregnancy in women with chronic hypertension, such as the benefits and risks, frequency, duration, and intensity. This prospective cohort study aims to investigate whether moderate-intensity daily physical activity reduces ambulatory blood pressure in pregnant women with chronic hypertension.

methodsPregnant women with chronic hypertension at 11+0 to 13+6 gestational weeks will be recruited from the outpatient clinic and divided into moderate- and light-intensity physical activity groups according to the intensity of the 7-day physical activity monitored using the model wGT3X-BT accelerometer. 24-h ambulatory blood pressure monitoring will be performed at enrollment as a baseline and will be repeated in the second and third trimesters. The primary outcome is the difference in the change in 24-h ambulatory systolic blood pressure from the first to the third trimester between the groups. Secondary outcomes include the difference of change in other ambulatory (24-h diastolic, daytime, and nighttime) and office blood pressure variables from the first to the second and third trimesters, the incidence of severe hypertension (≥160/110 mmHg), and changes in the type and dosage of antihypertensive medication. The primary and secondary outcomes related to changes in blood pressure from baseline to the second and third trimesters between the groups will be analyzed using Student's independent t-test or the Mann-Whitney U test. DISCUSSION: This cohort study will provide a basis for randomized controlled trials and verify an easily achieved, economical, and non-fetotoxic approach for adjuvant blood pressure management in pregnant women with chronic hypertension. REGISTRY: This study is registered with the Chinese Clinical Trials Registry (NO. ChiCTR2200062094). Date Registered: 21/07/2022.