Ultrasound fetal biometry and birth weight prognosis with the use of Aoki method and classical regression analysis

We have attempted to estimate prognostic value of neonatal birth weight prediction with the use of fetal sonographic data: biparietal diameter, femur length, transverse and longitudinal abdominal diameter. Clinical and ultrasound data from 265 pregnant women with singleton gestation who delivered within 7 days from the last ultrasound scan were analyzed. For the fetal weight estimation we have calculated fetal abdominal area in the equation proposed by Aoki in 1990. Predicted and observed neonatal birth weight centiles and coefficients of determination were calculated with the use of regression analysis. Prediction method of neonatal weight with Aoki method explained 70% of variability in our population. In contrast, regression analysis on ultrasound data explained 99% of observer variability in neonatal birth weight. We conclude that own method of birth weight prediction could be of value, however it should be tested in a new prospectively examined population.