Clinical significance of elevated mean arterial pressure in the second trimester.

Several reports suggested using the mean arterial blood pressure during the second trimester to predict the future development of preeclampsia. The value of a second-trimester mean arterial blood pressure greater than or equal to 90 mm Hg was reviewed in 39,876 reported cases of preeclampsia and 207 cases of eclampsia. The sensitivity ranged from 0% to 92% and the specificity varied from 53% to 97%. The predictive value of a positive test ranged from 0% to 43% and the predictive value of a negative test ranged from 76% to 98%. The predictive value of a positive test was not greatly higher than the incidence of hypertension in the whole population studied in the majority of the reports. There was a strong association of higher second-trimester mean arterial blood pressure in nulliparous women with eclampsia who had transient hypertension in later gestations and ultimately developed chronic hypertension. The data suggest that one sign of future chronic hypertension, that is, transient hypertension, is often predicted by high second-trimester mean arterial blood pressure, which may have the same significance. We think that if increased second-trimester mean arterial blood pressure levels predict anything, it is transient hypertension rather than preeclampsia-eclampsia.