Differences in visit-to-visit blood pressure variability between normotensive and hypertensive pregnant women.

We evaluated the relationship between blood pressure variability (BPV) and the development of hypertension during pregnancy. A total of 4163 pregnant women with normal blood pressure (BP) before 20 weeks of gestation were included in this study. The visit-to-visit blood pressure variability (VVV) was evaluated using the standard deviation (SD) of the systolic BP taken three times during pregnancy at approximately 10, 20, and 30 weeks of gestation. The VVV gradually decreased during pregnancy in normotensive subjects (SD: 7.2 ± 4.2 mmHg, 6.8 ± 3.9 mmHg, and 6.3 ± 3.6 mmHg at 10, 20, and 30 weeks, respectively). However, the VVV of hypertensive subjects did not decrease (SD: 8.2 ± 5.7 mmHg, 7.6 ± 5.0 mmHg, and 8.3 ± 5.3 mmHg at 10, 20, and 30 weeks, respectively) and was significantly greater than the VVV of normotensive subjects (p < 0.001). The VVV was significantly higher in patients who developed hypertension, and there was no decrease in VVV during pregnancy. Pregnancy complications were significantly increased in women with higher VVV at 10 and 30 weeks. Therefore, increased VVV during pregnancy may be a predictor of poor pregnancy outcomes.