AMBULATORY BLOOD-PRESSURE MONITORING IN PREGNANCY-INDUCED HYPERTENSION

Objective. To determine the role of ambulatory blood pressure monitori ng in the diagnosis of pregnancy-induced hypertension in women detecte d as hypertensive in the clinic by the conventional method. Design. An observational study of ambulatory blood pressure monitoring. Setting. A teaching hospital in Singapore. Methods. One hundred and twenty-eig ht women between 28-37 weeks of pregnancy diagnosed to have non-protei nuric pregnancy-induced hypertension in the clinic had 24 hours ambula tory brood pressure monitoring. The mean systolic and diastolic BP, sy stolic and diastolic white coat effect' and the diastolic load were th e main parameters noted. Results. One hundred and twenty subjects had valid recordings. Only 46 (38.3%) were found to be truly hypertensive on ABP monitoring, using a mean diastolic pressure cut off of 85 mmHg. The 'white-coat effect' was seen in both groups of women - the hypert ensives as well as the normotensives, although the magnitude of the wh ite coat effect had poor correlation with the clinic diastolic BP. A c ut-off value for diastolic load of 20 per cent was found to detect all hypertensives correctly (sensitivity 100%) with a modest false positi ve rate of 17.5 per cent. Conclusions. 'White-coat hypertension' is co mmon in pregnancy and ambulatory blood pressure monitoring would be he lpful in identifying the true hypertensive without requiring unnecessa ry hospitalization.