Placental growth factor as a diagnostic tool for placental mediated fetal growth restriction.

Abstract

Placental growth factor (PlGF) has shown promise in identification of placental fetal growth restriction (FGR). We aimed to investigate the association between PlGF and sonographic markers of placental dysfunction and assess its ability to diagnose FGR secondary to maternal vascular malperfusion (MVM). A retrospective study of singleton pregnancies with small for gestational age (SGA) fetuses, who had PlGF testing at 16-36weeks. Fetuses with major chromosomal and/or structural anomalies and pregnancies with missing outcomes were excluded. Sonographic characteristics, perinatal outcomes and placental histopathology were compared between pregnancies with normal and low PlGF (<10th percentile for gestational age). The diagnostic accuracy of PlGF for prediction of MVM was calculated. 130 fetuses met inclusion criteria. Compared to normal PlGF (n=65), pregnancies with low PlGF (n=65) were associated with an estimated fetal weight<5th centile (73.8% (48) vs 53% (35), respectively, p=0.01), abnormal uterine, umbilical and MCA Dopplers (p=0.001 for all), fetal demise (18.8% (12) vs 0% respectively, p=0.01) and preterm delivery (100% (65) vs 39% (59), respectively, p<0.001) . Low PlGF had a 70.1% (58.6-80.0) sensitivity and a 79.6% (64.7-90.2) specificity for identifying MVM, with an AUC of 0.73 (0.63-0.84). Positive and negative predictive values were 85.7% (76.8-91.2) and 60.3% (51.2-68.9), respectively. PlGF outperformed other parameters of placental FGR (uterine, umbilical artery, middle cerebral artery and abdominal circumference<5th centile), in isolation and when combined. PlGF is a useful tool to aid in the diagnosis of placental FGR secondary to MVM.