Chronobiologic ambulatory cardiovascular monitoring during pregnancy in Group Health of Minnesota

Chronobiologic cardiovascular screens are provided while reference standards for blood pressure and heart rate in uneventful pregnancies are collected for comparison with the nonpregnant state in health and for the evaluation of elevated risk and/or disease. Starting in the first or second timester, 66 women wore an ambulatory monitor manufactured by Colin Instruments for nearly two days. 92 such Minnesotan profiles during pregnancy are compared with profiles of 85 clinically healthy age-matched nonpregnant women. The overall range of change in a healthy pregnancy averages 58 and 40 mm Hg for systolic and diastolic blood pressure, respectively, and 47 beats per minute for heart rate. During pregnancy, the midline-estimating statistic of rhythm M (MESOR) is statistically significantly higher for heart rate and lower for blood pressure. Compared to the nonpregnant state, the circadian amplitudes of systolic and diastolic blood pressure are higher during pregnancy and are statistically significantly correlated with the questionnaire-assessed risk of developing high blood pressure and/or cardiovascular disease