Objective: To assess the accuracy of an automated blood pressure device (Microlife 3BTO-A) in pregnancy and pre-eclampsia according to the British Hypertension Society (BHS) protocol.
Design: Prospective observational study.
Setting: Antenatal ward and clinics at Guy's and St Thomas' Hospital, London, UK.
Population: One hundred and five pregnant women including 35 women with non-proteinuric hypertension and 35 with pre-eclampsia.
Methods: Two trained observers took nine sequential same-arm measurements from each woman. Measurements alternated between a mercury sphygmomanometer and the device.
Main outcome measures: Grading criteria of the BHS protocol (A/B grade = pass; C/D grade = fail).
Results: The device passed the BHS protocol by achieving an A/B grade. It also achieved criteria of the Association for the Advancement of Medical Instrumentation for systolic and diastolic pressures respectively, in normotensive [-0.5 (5.7) mmHg; -0.07 (7.7) mmHg], non-proteinuric hypertensive [-3.3 (6.9) mmHg; -2.4 (6.6) mmHg] and pre-eclamptic pregnancy [-4.1 (6.4) mmHg; -1.3 (7.9) mmHg].
Conclusion: The Microlife 3BTO-A can be recommended for use in a pregnant population, including pre-eclampsia, according to the BHS protocol.