Implementation of PlGF-based first-trimester screening and aspirin prophylaxis for preterm pre-eclampsia: clinical and economic evaluation.

Abstract

To evaluate the clinical effectiveness and economic impact of implementing first-trimester screening involving placental growth factor (PlGF) followed by aspirin prophylaxis for the prevention of preterm pre-eclampsia in routine obstetric practice. This retrospective cohort study was conducted at a tertiary maternal-fetal medicine center that implemented a first-trimester screen-and-prevent strategy for preterm pre-eclampsia. Two time periods were compared: a preimplementation phase (August 2011 to June 2014), during which risk assessment for pre-eclampsia was performed for research purposes without prophylactic aspirin administration; and a postimplementation phase (July 2017 to February 2024), during which women who screened as high risk for preterm pre-eclampsia were given aspirin prophylaxis (160 mg daily until 36 weeks' gestation). Risk assessment was based on the Fetal Medicine Foundation competing-risks algorithm, applied with and without the inclusion of PlGF. The primary outcome was the incidence of preterm pre-eclampsia (< 37 weeks). Secondary outcomes included preterm birth (< 37 weeks), overall pre-eclampsia and estimated healthcare cost savings based on national birth data. This model included the direct medical costs of neonatal management of preterm birth and lifetime costs of cerebral palsy. Adjusted odds ratios (aORs) for preterm pre-eclampsia were estimated using multivariable logistic regression analysis. Among 11 061 singleton pregnancies screened between 11 + 0 and 13 + 6 weeks' gestation, 3216 were screened during the preimplementation period and 7845 during the postimplementation period. The incidence of preterm pre-eclampsia declined from 1.1% to 0.6% between phases (aOR, 0.41 (95% CI, 0.25-0.68)). The overall rate of pre-eclampsia also decreased between phases (2.5% vs 1.4%; aOR, 0.51 (95% CI, 0.37-0.70)), as did that of preterm birth (5.9% vs 4.7%; aOR, 0.76 (95% CI, 0.63-0.92)). The protective effect of aspirin was most pronounced among women identified as high risk using a PlGF-based screening algorithm (aOR, 0.51 (95% CI, 0.28-0.92)), while no significant effect was observed in the group identified as high risk using an algorithm without PlGF. An economic model projected that this strategy would prevent 403 cases of preterm pre-eclampsia annually in a national cohort of 110 000 pregnancies, with estimated cost savings of €27.7 million. Real-world implementation of PlGF-based screening with aspirin prophylaxis significantly reduced the incidence of preterm pre-eclampsia and preterm birth, and was associated theoretically with substantial health-system cost savings. These findings support consideration of the nationwide adoption of early screen-and-prevent strategies for hypertensive disorders of pregnancy. © 2026 International Society of Ultrasound in Obstetrics and Gynecology.