What does an elevated mean arterial pressure in the second half of pregnancy predict--gestational hypertension or preeclampsia?

OBJECTIVE

The purpose of this study was to determine the predictive value of elevated mean arterial pressure in the second half of pregnancy for both preeclampsia and gestational hypertension.

STUDY DESIGN

This was a cohort of 588 nulliparous pregnant women studied prospectively from the twentieth week until delivery. Mean arterial pressure was obtained by means of a random-zero sphygmomanometer at 20, 26, and 31 weeks of gestation. The best cutoff point for the determination of predictive values was established by a receiver-operator characteristic curve.

RESULTS

Patterns of mean arterial pressure throughout pregnancy were different between preeclamptic and gestational hypertensive women. Receiver-operator characteristic curves for mean arterial pressure showed better predictive capacity for gestational hypertension than for preeclampsia. Sensitivity of mean arterial pressure to predict preeclampsia ranged between 39% and 48%, whereas for prediction of gestational hypertension it varied from 72% to 92%. Specificities for both groups were moderate (60% to 86%). Positive predictive values were low for all groups (5% to 33%).

CONCLUSION

Elevated mean arterial pressure in the second half of pregnancy is a good predictor of gestational hypertension but is a poor predictor of preeclampsia.