24-HOUR AMBULATORY BLOOD-PRESSURE MONITORING IN PREGNANT-WOMEN WITH CHRONIC HYPERTENSION - CAN IT PREDICT SUPERIMPOSED PREECLAMPSIA

Objective: To investigate if the 24-h ambulatory blood pressure (24-h ABP) monitoring technique could be useful in predicting the developmen t of preeclampsia in women with chronic hypertension. Design: A prospe ctive study in which 24-h ABP was measured in each trimester and 12 we eks postpartum. Method: Twelve women with untreated chronic hypertensi on had 24-h ABP monitoring performed with SpacLabs 90207 monitor; eigh t normotensive women served as controls. Results: In both the hyperten sive and the control group there was a nocturnal reduction of the bloo d pressure. However, when the 24-h blood pressure profiles were analyz ed separately for each woman, it was found that six women in the hyper tensive group and six women in the control group at least at one measu rement occasion during the pregnancy did not have any nocturnal blood pressure fall; one of the women in the hypertensive group developed pr eeclampsia. In the hypertensive group four women had no nocturnal bloo d pressure fall during the whole pregnancy, of these, one developed pr eeclampsia and one was subsequently in need of pharmacological treatme nt of the hypertension. When the 95% confidence limits for the hourly recordings of the hypertensive women with pregnancies without complica tions were calculated it was found that during the nighttime, two of t he women who subsequently developed preeclampsia had a blood pressure level at the upper limit whereas the other woman who developed that co ndition had a blood pressure level at or below the lower confidence li mit. Conclusion: The 24-h ABP monitoring technique in hypertensive pre gnancies seems to be of limited value in predicting the development of preeclampsia. The predictive value of an absent nocturnal blood press ure dip is limited as both normotensive and hypertensive women on seve ral occasions during pregnancy showed such absence.