Antenatal home blood pressure monitoring: a pilot randomised controlled trial

OBJECTIVE: To measure recruitment to, compliance with, and the acceptability of a trial designed to test whether a reduced schedule of antenatal visits combined with training in self-measurement of blood pressure at home may improve hypertension screening and save money. To test the specific hypothesis that even after taking into account extra unscheduled visits, the reduced schedule with ambulatory monitoring reduces total visits. DESIGN: A pilot randomised controlled trial. SETTING: Four urban and four rural general practices in Yorkshire and Lancashire. POPULATION: One hundred and five low risk women in the third trimester of pregnancy. Eighty women participated. INTERVENTION: Women were invited to participate at 24-28 weeks. Those who accepted were allocated either to a standard nine subsequent visit schedule (30, 32, 34, 36, 37, 38, 39, 40, 41 weeks) or to a reduced schedule (34, 38, 41 weeks). Those in the latter group measured their blood pressure weekly using a portable sphygmomanometer at home. MAIN OUTCOME MEASURES: Recruitment, total number of clinic visits, frequency of blood pressure measurement, schedule preference, and anxiety. RESULTS: Although there were more unscheduled visits in the home monitoring group, this did not outweigh the reduction in scheduled visits, (total visits reduced from 7 x 4 to 4 x 5, P < 0 x 001), and blood pressure was measured during more weeks (9 vs 7 weeks, P < 0 x 001) in the experimental group. Most women expressed a preference for the reduced schedule both when the idea was first suggested, and after they had experienced it, and there were no significant differences in anxiety. CONCLUSION: Replacement of antenatal screening visits with home blood pressure monitoring is acceptable to women. The reduction in clinic visits is not compensated by an increase in visits for other reasons and overall blood pressure measurement is omitted less often. Whether it reduces adverse outcomes or has any rare side effects will require a larger trial, but this pilot study indicates that it is likely to be safe, and that such a large trial would be feasible.