ASPRE trial: incidence of preterm pre-eclampsia in patients fulfilling ACOG and NICE criteria according to risk by FMF algorithm

Objective To report the incidence of preterm pre-eclampsia (PE) in women who are screen positive according to the criteria of the National Institute for Health and Care Excellence (NICE) and the American College of Obstetricians and Gynecologists (ACOG), and compare the incidence with that in those who are screen positive or screen negative by The Fetal Medicine Foundation (FMF) algorithm.

Methods This was a secondary analysis of data from the ASPRE study. The study population consisted of women with singleton pregnancy who underwent prospective screening for preterm PE by means of the FMF algorithm, which combines maternal factors and biomarkers at 11–13weeks’ gestation. The incidence of preterm PE in women fulfilling the NICE and ACOG criteria was estimated; in these patients the incidence of preterm PE was then calculated in those who were screen negative relative to those who were screen positive by the FMF algorithm.

Results A total of 34 573 women with singleton pregnancy delivering at ≥24 weeks’ gestation underwent prospective screening for preterm PE, of which 239 (0.7%) cases developed preterm PE. At least one of the ACOG criteria was fulfilled in 22 287 (64.5%) pregnancies and the incidence of preterm PE was 0.97% (95% CI, 0.85–1.11%); in the subgroup that was screen positive by the FMF algorithm the incidence of preterm PE was 4.80% (95% CI, 4.14–5.55%), and in those that were screen negative it was 0.25% (95% CI, 0.18–0.33%), with a relative incidence in FMF screen negative to FMF screen positive of 0.051 (95% CI, 0.037–0.071). In 1392 (4.0%) pregnancies, at least one of the NICE high-risk criteria was fulfilled, and in this group the incidence of preterm PE was 5.17% (95% CI, 4.13–6.46%); in the subgroups of screen positive and screen negative by the FMF algorithm, the incidence of preterm PE was 8.71% (95% CI, 6.93–10.89%) and 0.65% (95% CI, 0.25–1.67%), respectively, and the relative incidence was 0.075 (95% CI, 0.028–0.205). In 2360 (6.8%) pregnancies fulfilling at least two of the NICE moderate-risk criteria, the incidence of preterm PE was 1.74% (95% CI, 1.28–2.35%); in the subgroups of screen positive and screen negative by the FMF algorithm the incidence was 4.91% (95% CI, 3.54–6.79%) and 0.42% (95% CI, 0.20–0.86%), respectively, and the relative incidence was 0.085 (95% CI, 0.038–0.192).

Conclusion In women who are screen positive for preterm PE by the ACOG or NICE criteria but screen negative by the FMF algorithm, the risk of preterm PE is reduced to within or below background levels. The results provide further evidence to support the personalized risk-based screening method that combines maternal factors and biomarkers.

Fetal Medicine Foundation. Grant Number: 1037116

European Union 7th Framework Programme – FP7‐HEALTH‐2013‐INNOVATION‐2. Grant Number: 601852