Use of Placental Growth Factor (PLGF) for Aneuploidy Screening in Pregnancy: A Systematic Review [38K

Abstract

INTRODUCTION: Placental growth factor (PLGF) is a protein of trophoblastic origin. Whether addition of PLGF to combined serum aneuploidy screening tests improves detection rates for trisomy 21 is controversial. METHODS: We performed a systematic review of the literature until August 2019. We performed a goodness of fit test and retrieved the coefficient of determinations (R2) before and after the introduction of PGLF, as a function of false positive rates. Receiver-operating characteristic curves are provided in order to illustrate findings. RESULTS: We identified a total of 51 studies, of which 8 met inclusion criteria. Three prospective and five case-control studies included a total of 834 aneuploidy cases and 105,904 euploid control pregnancies. Detection rates (DR) were proportional to false-positive rates (FPR) across all studies, and ranged from 59.0% to 95.3% without the use of PLGF and 61.0% to 96.3% with PLGF (FPR 1% to 5%). Goodness of fit regression analysis revealed a logarithmic distribution of DR with R2=0.109 in the no PLGF group and R2=0.06 in the PLGF group. These indicate a large variation between DR for a given FPR across studies. Our analysis demonstrates average improvements in DR of 3.3% for a 1% FPR, 1.7% for a 3% FPR, and 1.4% for a 5% FPR. CONCLUSION: Addition of PLGF to prenatal screening using serum analytes mildly improves trisomy 21 detection rates between 1.4 and 3.3% for FPR’s between 5% and 1%, respectively. Future studies should address the cost-benefit analysis of introducing PLGF for prenatal screening.