54 Can we prevent recurrent pre-term preeclampsia?

Abstract

Preterm preeclampsia (PTPE) (<34 weeks of gestation) is a life-threatening complication of pregnancy with a high recurrence rate (20–60%). Low dose aspirin (ASA) may prevent recurrence, and some trials suggest that low molecular weight heparin (LMWH) and ASA together is more effective but results are inconclusive. We report the recurrence rate of PE in women with prior PTPE and the impact of therapy on fetal birth weight (BW) and gestational age at delivery (GA). We prospectively followed 41 women with PTPE in a prior pregnancy throughout 53 subsequent pregnancies. Women were screened for genetic and acquired thrombophilias and treated with either ASA or LMWH and ASA as determined by treating physicians. Maternal and fetal outcomes in subsequent pregnancies were ascertained including preeclampsia (PE), GA, and BW. The mean (±SD) age of the women was 36 ± 5 years at the time of their subsequent pregnancy, and BMI was 25.6 ± 5.4kg/m2. 66% were white, 5% black and 15% Hispanic. Genetic thrombophilias were detected in 91% and acquired thrombophilias in 36%. Thirteen women (25%) were not treated with ASA or LMWH, 12 (23%) received ASA alone, and 27 (52%) received LMWH ± ASA. PE recurred in 6 pregnancies (11%) and PTPE in 5 (9%). In subsequent pregnancies BW was higher (1473 ± 743 g prior pregnancy vs. 2880 ± 778 g in the subsequent pregnancies, p < 0.001), and GA at delivery was later (29 ± 4 weeks vs. 36 ± 4 weeks, p < 0.001). PE recurrence was numerically higher in the untreated group compared to those treated with ASA alone, or LMWH ± ASA (3/13 vs. 1/12 or 2/27). BW and GA increased similarly in subsequent pregnancies in all groups although women treated with LMWH ± ASA had a greater increase in GA (8.8 vs. 4.4 weeks, p = 0.021). The risk of recurrent PE or PTPE in women with prior PTPE was lower than reported in prior studies. BW and GA at delivery were significantly better in subsequent pregnancies. We found a trend towards a decreased incidence of PE and greater prolongation of pregnancy in those treated with LMWH ± ASA compared to no treatment or ASA alone. We propose an appropriately designed clinical trial to determine the benefits/risks of LMWH in women at risk for PTPE.