Blood pressure measurement for hypertension in pregnancy

Ambulatory BP monitoring (ABPM) has been proposed as a logical approach to overcoming many of the problems associated with clinical BP measurement. The extent of its use in diagnosing hypertension in pregnancy is unknown. The objective of this study was to identify the practices surrounding use of ABPM by practitioners to diagnose hypertension (HTN) and white coat hypertension (WCH) in pregnant women.

We mailed questionnaires to all obstetricians and family doctors practising obstetrics who were listed in the online medical directory of the College of Physicians and Surgeons of Alberta. Data were analyzed using SPSS.

Completed questionnaires were received from 81 obstetricians and 86 primary care physicians who manage hypertension in pregnancy. The majority of obstetricians (83%) and primary care physicians (79%) indicated that they "almost always" or "often" attempt to differentiate WCH from true HTN in pregnancy. The most popular method identified to differentiate WCH from true HTN in pregnancy was self (intermittent) home BP monitoring (78% of obstetricians and 69% of primary care physicians, P = 0.18). A minority of physicians in each group reported using ABPM to evaluate HTN in pregnancy, with significantly fewer obstetricians using ABPM diagnostically than primary care physicians (12% vs. 26%, P = 0.04).

Obstetrical care providers in Alberta are aware that WCH is an issue among pregnant women. While ABPM is chosen in a minority of cases, both obstetricians and primary care physicians appear to have a strong preference to use self BP monitoring for further BP evaluation.