Feature of trajectory of blood pressure among pregnant women with gestational hypertension

Objective: We aimed to describe the feature and the trajectory of blood pressure (BP) among pregnant women with onset of gestational hypertension. Methods: This epidemiology cohort study of pregnant women enrolled in Zhoushan, Zhejiang, included 4050 participants from the Zhoushan Pregnant Women Cohort. Each participant contributed up to eight serial perinatal visits of BP measurements from 2001 to 2018. Segmented mixed models were utilized to identify the dramatic change points in the relationship of BP elevation and gestational week among pregnant women with onset of gestational hypertension. Results: Despite of in which gestational week gestational hypertension developed, the SBP and DBP levels of pregnant women in each gestational hypertension category maintained the stable and normal levels (SBP <119∼130 and DBP <76∼83 mmHg) before the accelerated point. However, after the accelerated point, BP dramatically developed to gestational hypertension in a very short time period. Meanwhile, the earlier gestational hypertension onset was, the higher the baseline BP were; meanwhile, the earlier the gestational hypertension onset was, the higher the difference in BP at the gestational week of gestational hypertension onset between women with and without gestational hypertension was. Conclusion: BP trajectories of gestational hypertension onset in different gestational week presented similar patterns. Meanwhile, the earlier gestational hypertension onset was, the higher the baseline BPs were. These findings show that BP monitoring during pregnancy is necessary, especially for women with high normal baseline BP.