Cerebroplacental ratio and its relation to poor perinatal outcomes in singleton pregnancies: a cross sectional study in a tertiary care centre of Eastern India

Abstract

Background: Detection of fetal growth abnormalities by fetal monitoring is a critical component of perinatal care. Cerebroplacental ratio (CPR), as measured by colour Doppler, has recently been demonstrated to be a reliable indicator of foetus health. CPR is calculated as ratio of pulsatility index of middle cerebral artery (MCA) and umbilical artery (UA). When blood is redistributed in the early stages of hypoxia in favour of cerebral circulation, the diastolic flow amplitude increases above normal levels in MCA while umbilical flow in diastole decreases, providing CPR. This study aims to investigate the relationship between CPR and adverse perinatal outcomes. Methods: After institutional ethical approval, a 2-year study was conducted on 226 pregnant women of age group 18-45 years with singleton pregnancies at 34-38 weeks with informed consent in a tertiary hospital in Eastern part of India. The MCA and UA pulsatility index were calculated using a doppler scan on each patient. When the cerebroplacental ratio is <1 it is deemed abnormal. The perinatal outcomes were observed and their associations were evaluated. Results: There were 68/226 (30%) women had abnormal CPR (<1). CPR<1 was significantly associated with unfavourable perinatal outcomes (prematurity, low birth weight, NICU admission and perinatal hypoxia) with p value < 0.001. Conclusions: CPR is important tool in predicting an unfavourable perinatal outcome.