Biophysical and biochemical markers at 30-34 weeks' gestation in the prediction of adverse perinatal outcome

Objective: To investigate the potential value of biophysical and biochemical markers at 30 34 weeks’ gestation in the prediction of adverse perinatal outcome.

Methods: Screening study in 8,268 singleton pregnancies at 30 34 weeks. Estimated fetal weight (EFW), uterine artery pulsatility index (PI) PI), umbilical artery PI, fetal middle cerebral artery (MCA) PI, mean arterial pressure (MAP), serum placental growth factor (PLGF and soluble fms-like tyrosine kinase-1 (sFlt 1) were measured. The detection rate (DR) and false positive rate (FPR) of screening by each biomarker were estimated for stillbirth, preeclampsia, delivery of small for gestational age (SGA) neonate, cesarean section for fetal distress b efore or during labor, umbilical arterial cord blood pH <7.0 or umbilical venous blood pH <7.1, Apgar score <7 at 5 minutes and admission to the neonatal unit (NNU).

Results: Multivariable regression analysis demonstrated that significant predict ion of P E was provided by PLGF, sFlt 1, MAP and MCA PI with DR of 98% of PE delivering at <37 weeks’ gestation and 56% of those delivering at 37 weeks , at 10% FPR. Prediction of SGA was provided by EFW, PLGF, sFlt 1, uterine artery PI, umbilical artery PI, and MC A PI with DR of 88% of SGA at <37 and 51% at 37 weeks’ gestation, at 10% FPR. Prediction of stillbirth was provided by EFW, uterine artery PI and MCA PI with DR of 30 % at 10% Prediction
of cesarean section for fetal distress before labor was provided by EFW, sFlt 1, uterine artery PI and umbilical artery PI with DR of 90 %, at 10% FPR. Prediction of fetal distress in labor was provided by EFW and sFlt 1 with DR of 16 %, at 10% FPR. There were no significant differences from the normal outcome group in a ny of the biomarkers for low cord blood pH, low Apgar score or NNU admission for cases other than those with PE and / or SGA.

Conclusion: At 30 34 weeks’ gestation, biomarkers of impaired placentation and fetal hypoxemia provide good prediction of PE , SGA and fetal distress before labor, but poor or no prediction of stillbirth and adverse events in labor or after birth