Ambulatory blood pressure monitoring in pregnancy

Hypertensive disorders are among the most common medical complications of pregnancy and a leading cause of maternal and perinatal morbidity and mortality world-wide. Blood pressure measurement plays a central role in the screening and management of hypertension during pregnancy. In recent years the validity of conventional (clinic) blood pressure measurement has been questioned and efforts have been made to improve the technique with ambulatory automated devices that provide a large number of measurements over a period of time, usually a 24-hour period. This review focuses the application and the role of ambulatory blood pressure monitoring (ABPM) in non pregnant and pregnant individuals. The development of non invasive ambulatory blood pressure monitoring (ABPM) devices has been a great impetus to clinical hypertension research, and ABPM is now widely used in clinical practice. This position statement examines the evidence to support the use of ABPM, and provides guidance on how and when it should be applied in practice and how to interpret an ambulatory blood pressure (ABP) profile. A literature review of research in ABPM in pregnancy is presented, revealing good prediction of certain outcomes. The main topics addressed include the methodology of ambulatory blood pressure monitoring, its diagnostic and therapeutic thresholds, its clinical applications in hypertension, with specific reference to pregnant population, and its applications in research. I analyzed recently studies, whit an extensive database on complicated pregnancies, to assess the real applications of this technique in different obstetrics conditions. ABPM is then compared with different methods such as sphygmomanometer measurements or home blood pressure monitoring. The data show that blood pressure values obtained by 24-hour ABPM is superior in predicting low birth weight, prematurity and proteinuria, and the studies confirm that ambulatory blood pressure monitoring devices more accurately reflect a patient’s blood pressure and correlate more closely with end-organ complications than blood pressure levels measured in the physician’s office. These findings mirror the relevant areas in obstetric practice of improved diagnosis and identifying high risk pregnancy. Ambulatory blood pressure monitoring may be particularly helpful in clinical situations such as "white coat" hypertension and has a role in assessing apparent drug-resistant hypertension, symptomatic hypotension or hypertension, in the elderly, in hypertension in pregnancy and to assess adequacy of control in patients at high risk of cardiovascular disease. AMBP is also being increasingly used in clinical trials that assess the antihypertensive effects of medications. However, there are significant gaps in knowledge of the pathophysiology of the hypertensive disorders of pregnancy which hamper efforts to improve clinical care. In fact there is no randomized controlled trial evidence to support the use of ambulatory blood pressure monitoring during pregnancy. Randomized trials with adequate design and sample sizes are needed to evaluate the possible advantages and risks of ambulatory blood pressure monitoring during pregnancy, in particular in hypertensive pregnant women. Future research should also concentrate on randomized controlled trials that should evaluate not only clinical outcomes, but also use of health care resources and women's views.