P34.07: Ultrasound parameters of umbilical cord—reference values for normal pregnancy

Abstract

weight for adverse perinatal outcome in a group of small-forgestational age (SGA) fetuses. Methods: Data were collected from 105 singleton and nonmalformed fetuses suspected of being SGA during the third trimester and with a confirmed birth weight below the 10th centile. At diagnosis, estimated fetal weight was customized according to maternal and fetal characteristics and middle cerebral artery pulsatility index and umbilical artery pulsatility index were recorded, and tranformed to Z-values. Adverse perinatal outcome was defined as umbilical artery pH at delivery ≤7.15, 5-minutes Apgar score ≤7, significant neonatal morbidity (seizures, respiratory distress syndrome, necrotising enterocolitis, grade II-III intraventricular hemorrhage, hypoxic-ischemic encephalopathy), need of intubation, neonatal intensive care unit admission or neonatal mortality. Results: The prevalence of adverse perinatal outcome in our group of SGA fetuses was 50.5%. While the area under the curve (AUC) for Z-customized estimated fetal weight was 0.7 (95% CI, 0.59–0.81), for Z-umbilical artery Doppler was 0.5 (95% CI, 0.39–0.63) and for Z-middle cerebral artery was 0.55 (95% CI, 0.44–0.68). Paired analysis between parameters demonstrated that customized standards UAC was significantly larger than for both Doppler indices. Overall, the sensitivity and specificity for 10th centile cut-off of customized estimated fetal weight was 67.4% and 64%, respectively. Conclusion: In SGA fetuses, customized standards are a better predictor for adverse perinatal outcome than middle cerebral artery or umbilical artery Doppler indices.