Biology

Gestation

Labor induction

Fetus

Ischemia

Birth weight

Oxytocin

Genetics

Pediatrics

Neonatal intensive care unit

Gestational age

Internal medicine

Obstetrics

Medicine

Small for gestational age

Middle cerebral artery

Apgar score

Umbilical artery

Pregnancy

Fetal distress

Ultrasound in Obstetrics and Gynecology

ABSTRACT Objective To investigate the performance of screening for adverse perinatal outcome by the cerebroplacental ratio (CPR) measured within 24 h prior to induction of labor. Methods This was a prospective observational study of 1902 singleton pregnancies undergoing induction of labor at ≥ 37 weeks' gestation. Doppler ultrasound was used to measure the pulsatility index (PI) in the umbilical artery (UA) and fetal middle cerebral artery (MCA) within 24 h before induction of labor. The measured UA‐PI and MCA‐PI and their ratio were converted to multiples of the median after adjustment for gestational age. Univariable and multivariable logistic regression analysis was used to determine whether CPR improved the prediction of adverse perinatal outcome provided by maternal characteristics, medical history and obstetric factors. The detection rate (DR) and false‐positive rate (FPR) of screening by CPR were estimated for Cesarean section for presumed fetal distress and adverse neonatal outcome, which included umbilical arterial or venous cord blood pH ≤ 7 and ≤ 7.1, respectively, 5‐min Apgar score &lt; 7, admission to the neonatal intensive care unit for &gt; 24 h or hypoxic ischemic encephalopathy. Results A combination of maternal and pregnancy characteristics, including age, weight, racial origin, previous obstetric history, pre‐eclampsia, gestational age at delivery and amniotic fluid volume, identified 39% of pregnancies requiring Cesarean section for fetal distress at a FPR of 10%; addition of CPR did not improve the performance of screening. In screening for adverse neonatal outcome by a combination of parity and CPR, the DR was 17% at a FPR of 10%. Conclusion Low CPR, measured within 24 h prior to induction of labor, is associated with increased risk of Cesarean section for fetal distress and adverse neonatal outcome, but the performance of CPR for such surrogate measures of fetal hypoxic morbidity is poor. Copyright © 2018 ISUOG. Published by John Wiley &amp; Sons Ltd.

Prediction of adverse perinatal outcome by cerebroplacental ratio in women undergoing induction of labor