No difference between home and clinic blood pressure measurements in pregnancy: a computerized telemetric study

Many decisions in pregnancy are based on one or two casual blood pressure estimations made in the antenatal clinic. No previous study has challenged the validity of this practice or attempted to discover whether there are significant differences between the blood pressures of pregnant women when they are measured in the clinic and when they are measured in their home environment. We measured the blood pressures of 35 healthy pregnant women both at the antenatal clinic and in their own homes. All the women were at between 28 and 32 weeks gestation. At both locations, ten consecutive blood pressure and pulse measurements were made at one minute intervals using a Dinamap 1846P automated blood pressure monitor. The readings taken in the clinic were supervised, whilst at home the patients used our blood pressure telemetry system without direct supervision, the results being transmitted automatically to the hospital computer via the public telephone network. The Dinamap results were analysed in detail. Each ten minute recording session was summarised in terms of the first, last, highest, lowest and mean of the systolic, diastolic and mean arterial blood pressure, and pulse measurements in that session. Also, two measures of the variability within a ten measurement series were considered, the average change in pressure or pulse from one reading to the next, and the difference between the highest and lowest readings of pressure and pulse in the series. All descriptors of the clinic and the home measurements were compared using the paired Student's t-test. Clinic and home blood pressure measurements were not significantly different from each other in any respect.(ABSTRACT TRUNCATED AT 250 WORDS)