The Circadian Rhythm of Blood Pressure During Pregnancy

To review the literature on the circadian rhythm of blood pressure during pregnancy. Data Sources : Computerized searches on MEDLINE, CINAHL, and MIRLYN. Study Selection : Selected studies from 1969 to 1997 were evaluated. Data Extraction : Data were extracted and information was organized under the following areas: definition of and the interconnection between circadian rhythm and blood pressure; the circadian variability of blood pressure throughout the trimesters; the patterns of the circadian rhythm of blood pressure in pregnancies defined as normal and those complicated by chronic hypertension and preeclampsia; and clinical implications. Data Synthesis : The circadian rhythm of blood pressure in pregnancy is the same as in the nonpregnant state, with a nocturnal decrease, especially during sleep. In patients with chronic hypertension, the nocturnal fall in blood pressure may be steeper. Patients with mild preeclampsia may experience a less pronounced nocturnal decrease in blood pressure. Patients with severe preeclampsia may display a reversed circadian rhythm, with no decrease and/or an increase in nocturnal blood pressure. Conclusions : The patterns of the circadian rhythm of blood pressure during normal pregnancy and pregnancies complicated by chronic hypertension and preeclampsia warrant consideration when monitoring patients and implementing management plans.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71412/1/j.1552-6909.2000.tb02771.x.pd