The association between pentraxin 3 in maternal circulation and pathological intrauterine fetal growth restriction

To assess the diagnostic accuracy of maternal serum pentraxin 3 (PTX3) in identifying pathological intrauterine fetal growth restriction (IUFGR) among women presented in the third trimester of pregnancy with a small for gestational age (SGA) fetus.

This case control study was conducted in Ain-Shams University Maternity Hospital, Abbasiya Square, Cairo, Egypt and included women diagnosed at the third trimester of pregnancy as having a SGA fetus. Cases included pregnant women with pathological IUFGR, while women with physiologically SGA fetus were included in the control group. Diagnosis of antenatal SGA fetus was based on the presence of abdominal circumference <10th percentile. Pathological IUFGR was provisionally diagnosed antenatally by the presence of falling percentiles on serial ultrasound scans and then the definitive diagnosis was established postnatally after comprehensive neonatal evaluation. Maternal venous blood samples were collected from the eligible participants, once at the time of enrollment, to assess serum PTX3 levels using enzyme-linked immunosorbent assay (ELISA). Both groups were then followed up till delivery to confirm the diagnosis.

Among the 68 pregnant included in the study, PTX3 was found to be significantly elevated in women with SGA fetus due to pathological IUFGR (n=34) than those with physiologically SGA fetus (n=34) [6.5 ng/ml (2.5-11.0) versus 1.2 ng/ml (0.8-2.5) respectively], with a best cutoff value of ≥1.3 ng/ml [sensitivity of 85.3% (95% confidence interval (CI), 68.9-95.0) and a specificity of 73.5% (95% CI, 55.6-87.1)]. Using multivariable binary logistic regression model, amniotic fluid index (AFI) (P=0.010), estimated fetal weight (EFW) (P=0.016), PTX3 level (P=0.041), and umbilical artery pulsatility index (UA-PI) (P=0.027) were all found to be independent diagnostic markers for pathological IUFGR.

PTX3 is a promising marker that deserves further evaluation as it may differentiate normal and abnormal fetal growth among women presenting at third trimester of pregnancy with a SGA fetus.