Daily blood pressure patterns in healthy and hypertensive pregnant women

With the aim to describe the circadian pattern of non-invasive ambulatorily monitored blood pressure (BP) during pregnancy in clinically healthy women as well as in pregnant women who developed gestational hypertension or preeclampsia, the authors analyzed 759 BP series sampled for about 48 hours every four weeks after the first obstetric visit in 71 women with uncomplicated pregnancies and 42 with gestational hypertension or preeclampsia. The circadian pattern of BP variation for each group (complicated vs. uncomplicated pregnancies) and trimester of gestation was established by linear least-squares methods. A highly statistically circadian pattern is demonstrated for systolic (SBP) and diastolic BP (DBP) for both groups of pregnant women in all trimesters (p<0.001 in all cases). The differences in circadian rhythm-adjusted mean between complicated and uncomplicated pregnancies are highly statistically significant in all trimesters (p always <0.001). This study confirms and extends to ambulatory everyday life conditions the predictable circadian variability in BP during gestation. The differences in BP between healthy and complicated pregnancies can be observed as early as in the first trimester of pregnancy. Those differences are found when both SEP and DBP for women with a later diagnosis of gestational hypertension or preeclampsia are well within the accepted normal physiologic range of BP variability.