A clinical evaluation of placental growth factor in routine practice in high-risk women presenting with suspected pre-eclampsia and/or fetal growth restriction

Abstract

Objective: To evaluate the use of plasma Placental Growth Factor (PlGF), recommended by the recent NICE guidance, in women with suspected pre-eclampsia (PE) and/or fetal growth restriction (FGR).

Study design: Non-randomised prospective clinical evaluation study in high-risk antenatal clinics in a tertiary maternity unit.

Methods: PlGF testing was performed in addition to routine clinical assessment in 260 women >20 weeks' gestation with chronic disease (hypertension, renal disease ± diabetes) with a change in maternal condition or in women with suspected FGR to determine the impact on clinical management. Results were revealed and standardised care pathways followed.

Main outcome measures: Outcome of pregnancies with a low PlGF (<12 pg/ml and 13-100 pg/ml), impact on clinical service and the diagnostic accuracy of alternative PlGF cut-offs.

Results: 206/260 (79.2%) women had an adverse outcome (PE/birthweight < 10th centile/preterm birth). In our cohort, a low PlGF (<12 pg/ml) was associated with a shorter test-birth interval and universally (100% PPV) with an adverse pregnancy outcome, although 29/61 (47.5%) of women with PlGF < 12 pg/ml continued their pregnancy >14 days. The PlGF result altered clinical management (surveillance or timing of birth) in 196/260 (75.4%) cases. Alternative PlGF thresholds did not significantly improve diagnostic performance.

Conclusions: Our evaluation confirms the value of PlGF as a diagnostic tool for placental dysfunction. However, low PlGF in isolation should not trigger iatrogenic delivery. Further research linking placental pathology, maternal disease and maternal PlGF levels is urgently needed before this test can be implemented in routine clinical practice.

Keywords: Fetal growth restriction; High-risk pregnancy; Placental growth factor; Pre-eclampsia; Preterm delivery; Small for gestational age.