OBJECTIVES: The aim of this study was to asses the correlation of middle cerebral artery pulsatility index (MCA-PI) and perinatal outcomes in prolonged pregnancies.
STUDY DESIGN: This was a prospective study of all consecutive pregnant women beyond 41 weeks’ gestation attending for obstetric surveillance during a two years period. We evaluated the predictive value of MCA-PI lower than the 5th percentile (<p5) and the occurrence of: cesarean delivery for fetal distress, 5-min Apgar score <7, arterial cord pH < 7.15, presence of thick meconium at delivery, need for admission to the neonatal intensive care and/or neonatal death.
RESULTS: Three hundred and one pregnancies met the inclusion criteria and were managed expectantly. Of them, 31 (10.3%) fetuses had an MCA-PI < p5, which showed a significant relationship with the presence of thick meconium at birth (p < 0.001), but was not related to any of the other perinatal outcomes.
CONCLUSIONS: prolonged pregnancies, the finding of MCA-PI < p5 is related to meconium emission at the time of delivery, but is not associated with an increased risk of adverse perinatal outcome.