The value of middle cerebral artery-umbilical artery pulsatility index ratio in prediction of severe fetal growth restriction

Abstract

Objective: To evaluate the value of the ratio of middle cerebral artery pulsatility index(MCA PI) to the umbilical artery pulsatility index (UA PI) for predicting of adverseperinatal outcome in the fetal growth restriction (FGR).

Materials and methods: A prospective study was performed on 82 pregnant women in Thammasat University Hospital between January 1, 2009 and December 31, 2009. The studypopulation comprised 27 pregnant women who delivered FGR fetuses and 55pregnant women whose fetuses were normal growth. The MCA PI, UA PI andMCA PI/ UA PI ratio were assessed. Mild and severe FGR were defined asa fetus having the fetal weight below the 10^th and 5^th percentile, respectively.Abnormal MCA PI/ UA PI (CU ratio) were defined as the ratio < 1.08.

Results: Of the 82 pregnant women, In FGR cases have high oligohydramnios, highcesarean section rate, lower GA at delivery, low birth weight and high rateof neonatal intensive care unit (NICU) admission compared with normal cases(P<0.05). 8 out of 27 women with FGR showed abnormal CU ratio but only2 in 55 fetuses in normal group (P <0.001). Among these, mild and severeFGR with abnormal CU ratio were 5 (26.3%) and 3 (37.5%), respectively whichwas demonstrated not significantly difference (P = 0.658).

Conclusion: The MCA PI/ UA PI ratio could not be used as the predictor of the severeFGR from mild FGR in a particularly severe case of FGR.

Key words: Doppler Ultrasound, Fetal growth restriction, Cerebro-umbilical ratio, Middlecerebral artery, Umbilical artery