Antithrombin plasma levels decrease is associated with preeclampsia worsening

Antithrombin plasma levels (AT) have been found decreased in women with preeclampsia (PE), but little is known about the trend of AT during the course of this disease. We prospectively investigated AT in consecutive women admitted to our hospital with a diagnosis of PE, to assess if AT fluctuations could be associated with the evolution of the disease. AT, platelet count and D-dimer levels were determined every other day. In the 73 patients studied, AT, platelet count and fibrinogen progressively reduced during the observational period, reaching a nadir on the day of delivery, whereas D-dimer progressively increased over time. Statistical analysis was restricted to the 39 women that had an AT measurement performed on each of days -1, 0 and +1, with respect to the day of delivery. These subjects showed a significant decrease in AT on the day of delivery compared to the day just before (77.8 +/- 15.1%vs. 85.4 +/- 14.2%, P = 0.027), followed by a recovery on the first day after delivery (87.6 +/- 21.3% from 77.8 +/- 15.1%, P = 0.005). Our study demonstrates that a significant drop in AT levels is associated with the clinical worsening of PE, regardless of its severity.