Fetal Trans-Cerebellar Diameter to Abdominal Circumference (TCD/AC) Ratio in Assessment of Gestational Age for The Prediction of Normal Fetal Growth and Intrauterine Growth Restriction

Background: An accurate gestational age (GA) is the most critical parameter required for the proper management of expectant women. The head circumference (HC), abdominal circumference (AC), biparietal diameter (BPD), and femoral length (FL) are fetal biometric parameters that are frequently employed. These parameters are nonspecific and are contingent upon precise perinatal growth measurements and actual menstrual age.This study aimed to Evaluation of GA for the prediction of normal fetal growth and intrauterine growth restriction (IUGR): Evaluate the precision of the fetal trans-cerebellar diameter (TCD)/AC ratio. Methods This a cross-sectional study included 100 pregnant women, All patients underwent routine obstetric ultrasound scanning. Results: A significant positive correlation between TCD/ AC and BPD (r=0.065, P= 0.048), FL (r=0.246, P=0.013), HC (r=0.234, P=0.019), TCD (r=0.275, P< 0.001) and a significant negative correlation between TCD/ AC and AC (r=- 0.770, p< 00001). TCD/AC with area under curve of 0.869 can significantly predict the incidence of IUGR (P<0.001), at cut off value of >13.7, with 71.79% sensitivity, 80.33% specificity, 70% positive predictive value and 81.7% negative predictive value. Conclusion: TCD to AC ratio can be used to assess GA because it had high accuracy in predicting the incidence of intrauterine growth retardation at cut off value of >13.7. Neonates with intrauterine growth retardation may have low fetal biometric parameters, FL, HC, AC, and TCD.