Twenty‐four‐hour and conventional blood pressure components and risk of preterm delivery or neonatal complications in gestational hypertension

Gestational hypertension is a recognized risk factor for the development of complications during pregnancy. The present study retrospectively assessed the respective values of blood pressure components derived from conventional and 24-h recordings (ABPM) as predictors of premature delivery in women with gestational hypertension based on office readings from 26th week of gestation onwards. Blood pressures were measured conventionally and over 24 h. Standard medical and obstetric history, and standard laboratory work-up were taken into account. The mean (+/- standard deviation, SD) age of 123 women was 29 +/- 6 years. Current pregnancy was, on average, the second. The conventional systolic (SBP)/diastolic (DBP) blood pressure averaged 140 +/- 19/92 +/- 14 mmHg, and pulse pressure (PP) and mean arterial pressure (MBP) averaged 48 +/- 10 and 108 +/- 15 mmHg. The corresponding values derived from ABPM were 135 +/- 16/90 +/- 11, 47 +/- 9 and 105 +/- 12 mmHg. The 24-h blood pressures had better prognostic value than the conventional blood pressures. The 24-h SBP predicted risk of premature delivery and was inversely related to the duration of pregnancy and birth weight. After the exclusion of 41 women with white-coat hypertension, the highest predictive value was associated with PP. PP wider by 1SD was associated with 66% higher risk of premature delivery, and was associated with shortening of pregnancy by 2 weeks and 400 g lower birth weight, even after adjustment for SBP. In conclusion, ABPM is superior to conventional blood pressure measurements in predicting adverse outcome of pregnancy. Twenty-four-hour PP, of all classic indices, seems to be most closely related to increase of that risk.