Ultrasonic evaluation of transverse cerebellar diameter and vermian anteroposterior diameter in detecting fetal age among pregnant Egyptian women

Abstract

Background Accurate dating of pregnancy is critically important for pregnancy follow-up from the first trimester to delivery and is particularly necessary for determining viability in premature and postdate deliveries. Aim The aim of the present study was to determine the accuracy of fetal transverse cerebellar diameter (TCD) and vermian anteroposterior diameter as ultrasonographic parameters for the prediction of fetal age. Patients and methods Five hundred and twenty normal pregnant women were examined for the TCD depending on the fetal age of their fetuses from 14 to 38 weeks. Four hundred and sixty normal pregnant women out of the previous were examined for vermian anteroposterior diameter from 18 to 38 weeks. The data analyzed by SPSS were used to calculate mean±SD for quantitative variables. Percentiles 5th, 50th and 95th, Pearson correlation and polynomial regression were also used. Results The mean TCD increased from 13.63 mm at 14th week to 53.68 mm at 38th week of gestation. There was high degree of correlation between TCD and fetal age. The mean vermian anteroposterior diameter increased from 8.78 mm at 18th week to 26.68 mm at 38th week of gestation. There was a linear correlation between vermian anteroposterior diameter and fetal age. There was linear correlation between TCD and vermian anteroposterior diameter. Conclusion It could be concluded that the TCD and vermian anteroposterior diameter are reliable parameters for the determination of fetal age in the second and third trimesters of pregnancy.