Effect of regular exercise on blood pressure in normotensive pregnant women. A randomized controlled trial

Objective: To evaluate the effect of regular exercise on maternal arterial blood pressure (BP) at rest and during uphill walking, in healthy former inactive pregnant women. Methods: A single-blind, single-center, randomized controlled trial including 61 out of 105 healthy, inactive nulliparous pregnant women, initially enrolled in a controlled trial studying the effect of 12 weeks of aerobic exercise (60 min 2/week) on maternal weight gain. Primary outcome was the mean adjusted difference in change in resting systolic and diastolic BP from baseline to after intervention. Secondary outcome was the mean adjusted difference in change in systolic BP during uphill treadmill walking at critical power. Measurements were performed prior to the intervention (gestation week 17.6 +/- 4.2) and after the intervention (gestation week 36.5 +/- 0.9). Results: At baseline, resting systolic and diastolic BP was 115/66 +/- 12/7 and 115/67 +/- 10/9 mmHg in the exercise (n = 35) and control group (n = 26), respectively. After the intervention, resting systolic BP was 112 +/- 8 mmHg in the exercise group and 119 +/- 14 mmHg in the control group, giving a between-group difference of 7.5 mmHg (95% CI 1.5 to 12.6, p = 0.013). Diastolic BP was 71 +/- 9 and 76 +/- 8 mmHg, with a between-group difference of 3.9 mmHg (95% CI -0.07 to 7.8, p = 0.054). During uphill treadmill walking at critical power, the between-group difference in systolic and diastolic BP was 5.9 mmHg (95% CI -4.4 to 16.1, p = 0.254) and 5.5 mmHg (95% CI -0.2 to 11.1, p = 0.059), respectively. Conclusions: Aerobic exercise reduced resting systolic BP in healthy former inactive pregnant women.