Ambulatory versus conventional methods for monitoring blood pressure during pregnancy

Not enough evidence to show whether wearing a blood pressure monitoring device for 24 hours during pregnancy is better at detecting hypertension than clinic tests.

High blood pressure (hypertension), when associated with protein in the urine (pre-eclampsia), can lead to serious complications during pregnancy. Measuring and monitoring blood pressure has therefore been a central feature of pregnancy care. However, the value of one-off measurements at a clinic visit have been questioned. Blood pressure measurement devices have been developed which the woman wears during her normal activities. These take several measurements, usually over a 24-hour period (ambulatory blood pressure monitoring). The review of trials found there was no evidence to assess the effects of ambulatory blood pressure monitoring during pregnancy.

Authors' conclusions: 

There is no randomised 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. These trials should evaluate not only clinical outcomes, but also use of health care resources and women's views.

[Note: The three citations in the awaiting classification section of the review may alter the conclusions of the review once assessed.]

Read the full abstract...

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.


To assess whether the use of ambulatory blood pressure monitoring during pregnancy improves subsequent maternal and feto-neonatal outcomes, women-newborn quality of life or use of health service resources, compared with conventional (clinic) blood pressure measurements. These effects will be assessed for the following subgroups: (1) Women at low or average risk of hypertensive disorders of pregnancy (unselected). (2) Women defined as high risk of hypertensive disorders of pregnancy. (3) Women with hypertension without other signs of pre-eclampsia. (4) Women with established pre-eclampsia.

Search strategy: 

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (January 2005), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2005), MEDLINE (January 2005), LILACS (July 2001) and EMBASE (April 2005) were searched. We updated the search of the Cochrane Pregnancy and Childbirth Group's Trials Register on 14 March 2011 and added the results to the awaiting classification section.

Selection criteria: 

All randomised trials comparing ambulatory blood pressure monitoring versus conventional (clinic) blood pressure monitoring in pregnancy. Quasi-random designs will be excluded.

Data collection and analysis: 

Two reviewers evaluated all potentially relevant articles, examined each study for possible inclusion and assessed the methodological quality using the Cochrane guidelines.

Main results: 

No trials included.