Cerebroplacental Ratio as a Predictor of Fetal Growth Restriction and Perinatal Outcome in Women with Hypertensive Disorder in Pregnancy: A Prospective Cohort Study

Abstract

Introduction: Hypertensive Disorders in Pregnancy (HDP), is a common complication of pregnancy leading to majority of adverse perinatal outcome. The timely diagnosis of fetal compromise, before irreversible damage, is possible by doing Cerebroplacental Ratio (CPR), on doppler ultrasonography. CPR is calculated as ratio of Pulsatility Index (PI) of Middle cerebral Artery and Umblical Artery (UA). It reflects both the circulatory insufficiency in UA along with adaptive changes in Middle cerebral Artery (MCA). Aim: To evaluate role of Cerebroplacental Ratio as predictor of Fetal Growth Restriction and perinatal outcome in singleton pregnancy with HDP at 28-41 weeks of gestation. Materials and Methods: A prospective observational cohort study was carried out in the Department of Obstetrics and Gynaecology, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi, India. The study included 150 women with singleton pregnancy, HDP and 28-41 weeks of gestation. Doppler ultrasound was performed and CPR calculated as ratio of MCA PI and UA PI, using ultrasound study performed within two weeks of delivery. All women were followed-up till delivery and perinatal outcome i.e., birth weight, preterm birth, cesarean for fetal distress, Meconium Stained Liquor (MSL) , APGAR at 5 minutes, still birth, Neonatal Intensive Care Unit (NICU) admission and early neonatal death, were recorded. The data entry was done in the Microsoft excel spreadsheet and the final analysis was done with the use of Statistical Package for Social Sciences (SPSS) software version 21.0. Results: Out of 150 women, 20% (30) had abnormal CPR. Abnormal CPR had significant association with Low Birth Weight (LBW) (p-value=0.0001), preterm delivery (p-value=0.0001), fetal distress (p-value=0.0001), caesarean for fetal distress (p-value=0.0001), 5-minute APGAR score <7 (p-value=0.0001), NICU admission (p-value=0.0001), Meconium Stained Liquor (MSL) (p-value=0.0001) and neonatal death (p-value=0.025). CPR had 100% sensitivity and 100% Negative Predictive Value (NPV) for predicting adverse perinatal outcome with diagnostic accuracy of 47.33%. Conclusion: The CPR is an independent predictor of Fetal Growth Restriction (FGR) in women with HDP. It can also independently predict perinatal outcome in women with HDP with or without FGR. Abnormal CPR had 100% sensitivity for identifying women with high risk of adverse perinatal outcomes, whereas normal CPR, with NPV of 100%, almost excludes it.