Ambulatory Blood Pressure Measurement in Pregnancy: the Current State of the Art

Abstract

Blood pressure measurement is one of the most frequently used screening tests in pregnancy. However, conventional blood pressure measurement has several shortcomings; it provides a measurement that represents only a fraction of the 24-h blood pressure profile, usually under circumstances that may have a pressor effect, and the technique is fraught with potential errors. In the nonpregnant population the development of devices capable of accurately measuring 24-h blood pressure noninvasively is proving valuable in predicting the cardiovascular complications of hypertension. It is likely that this technique will also prove useful in pregnancy. Validation in pregnancy of such monitoring techniques should precede any widespread application. Reference values using oscillometric monitors are now available for 24-h ambulatory blood pressure measurement in pregnancy. Provisional data suggest that ambulatory blood pressure measurement could overcome the large sampling, measurement, and “white coat hypertension phenomenon” errors associated with conventional measurement. In addition, changes in the diurnal rhythm of blood pressure may have diagnostic significance in the prediction of preeclampsia. Outpatient monitoring using 24-h ambulatory blood pressure devices may reduce the need for inpatient assessment, which has very considerable implications in terms of cost and patient satisfaction.