First trimester pre-eclampsia screening using FMF-UtA-PAPPA algorithm in Hong Kong: A low-cost alternative to PlGF

OBJECTIVE: To evaluate the effectiveness of Fetal Medicine Foundation-based first-trimester preeclampsia (PE) screening using maternal factors, mean arterial pressure, uterine artery Doppler and pregnancy-associated plasma protein-A, without placental growth factor (FMF-UtA-PAPPA), versus the maternal history approach (National Institute for Health and Care Excellence criteria - NICE approach), when implemented in a public non-academic setting with a predominantly East Asian population. MATERIALS AND METHODS: Retrospective, non-intervention study involving 1860 pregnancies who received PE screening from 1/5/2022 to 31/12/2023 and subsequently delivered within our system. The NICE approach was retrospectively applied to the cohort. For those who received aspirin, adjustments were made for its effect in reducing preterm PE. Primary outcomes were detection rates of preterm and term PE, while secondary outcomes were delivery outcomes of those with preterm PE. RESULTS: The FMF-UtA-PAPPA approach was superior to the NICE approach in preterm PE detection (80% vs 55%, p = 0.031) and in total PE detection (67.8% vs 45.8%, p = 0.015). Those that eventually developed preterm PE had significantly worse fetal outcomes including lower gestational ages (32.3 vs 38.8 weeks, p < 0.001), lower birth weights (1499 vs 3044 g, p < 0.001), and higher rates of neonatal unit admission (66.7% vs 15.4%, p < 0.001). CONCLUSION: First trimester PE screening by the FMF-UtA-PAPPA approach provides superior detection rates compared to the existing NICE approach in our predominantly East Asian population. This add-on to combined first trimester trisomy screening is low-cost and does not require laboratory investment, but still identifies many more high-risk pregnancies that would benefit from low-dose aspirin, thereby preventing many cases of preterm PE and their maternal-fetal complications.