Association between abnormal late third trimester cerebroplacental ratio and perinatal outcomes in appropriate for gestational age fetuses

Abstract

Background: A significant proportion of adverse perinatal outcomes occurs in appropriately grown fetuses. There is therefore need for  additional measures to screen for those fetuses at risk of hypoxia besides the estimated fetal weight and abdominal circumference.

Objectives: To determine the association between abnormal cerebro- placental ratio and adverse perinatal outcomes in appropriate for  gestational age fetuses.

Study Design: A retrospective cohort study was conducted. The association between cerebroplacental ratio below the 10th centile and  composite adverse perinatal outcomes was sought. Multivariable logistic regression analysis was conducted to control for potential  confounding variables.

Results: A total of 150 participants with appropriate for gestational age fetus between 36-38 weeks were assessed for cerebroplacental  ratio. Of these 21(14%) had a cerebroplacental ratio below the 10th centile. The cumulative composite adverse perinatal outcomes were  observed in 15 cases (10%). Of the 15 cases, only 2 (13%) had a cerebroplacental ratio below the 10th centile (p=1.000). No stillbirth, Apgar  score < 7 at 5 minutes or NICU admission occurred. There was no difference in perinatal outcomes, maternal demographics,  gestation at delivery, and mode of delivery in both groups. Overall, cerebroplacental ratio performed poorly as a predictor of adverse  perinatal outcomes in AGA fetuses; aOR 1.08 (95% C.I: 0.25,7.43 p=0.99).

Conclusion: There was no association between abnormal  cerebroplacental ratio and composite adverse perinatal outcomes in appropriate for gestational age fetuses and it is therefore not a  useful index in the assessment of fetal wellness in this cohort.