OP12.01: Risk assessment for pre‐eclampsia in nulliparous women at 11 to 13 weeks gestational age: evaluation of two algorithms

This prospective study aimed to evaluate two algorithms for prediction of pre-eclampsia in a population of nulliparous women in Norway. The study was conducted at National center for fetal medicine in Trondheim, Norway. 541 nulliparous women were examined between 11 + 0 and 13 + 6 weeks with interviews for maternal characteristics and measurements of mean arterial pressure, uterine artery pulsatility index, pregnancy associated plasma protein A and placental growth factor. The First Trimester Screening Program version 2.8 by The Fetal Medicine Foundation (FMF) was compared with the Pre-eclampsia Predictor TM version 1 revision 2 by Perkin Elmer (Predictor). Receiver operating characteristic curves and test characteristics were evaluated. Twenty-one women (3.9%) developed pre-eclampsia. The two algorithms performed equally well for prediction of pre-eclampsia requiring delivery before 42 weeks with area under the curve of 0.77 (0.67-0.87) and sensitivity 40% (95% CI 19.1-63.9) at a fixed 10% false positive rate for FMF and 0.74 (0.63-0.84) and sensitivity 30% (95% CI 11.9-54.3) at a fixed 10% false positive rate for Predictor. The FMF algorithm performed well for preterm pre-eclampsia (delivery < 37 weeks) with area under the curve of 0.94 (0.86-1.0) and sensitivity of 80% (95% CI 28.4-99.5) at a 10% fixed false positive rate. FMF and Predictor algorithms had similar and only modest performance in predicting pre-eclampsia requiring delivery before 42 weeks. The FMF algorithm may be suitable for prediction of preterm pre-eclampsia.