The value of fetal trans cerebellar diameter in detecting GA in different fetal growth patterns in Egyptian fetuses

Ultrasonographic assessment of fetal gestational age is very critical for clinical decision making in obstetrics, many fetal biometric parameters are extensively used but in this research study we mainly targeted transcerebellar diameter in second and third trimester among Egyptian population and its accuracy and clinical reliability to calculate fetal gestational age. Aim of the research: The main goal and corner stone purpose of this research was to measure the accuracy of the transcerebellar diameter Transcerebellar diameter in calculating the gestational age of fetuses among Egyptian population and if it is more accurate than other fetal biometric measurements (Biparietal diameter, Head circumference, Abdominal circumference, Femur Length) in gestations with no medical disorders or not and the additional different methodology implemented in this research in comparison to other studies was using the Transcerebellar diameter in diabetic mothers with macrosomic fetuses, in pregnant Egyptian ladies with hypertension during pregnancy that have growth restricted fetuses with evaluation of uteroplacental blood flow by Doppler flow indices confirming uteroplacental insufficiency, also in fetuses with congenital structural abnormalities and in cerebellar anomalies. Results: The IQR interquartile range of the discrepancy between menstrual and sonographic gestational ages was the least when Transcerebellar diameter, in comparison to Biparieteal Diameter, Head Circumference, Abdominal Circumference and Femur Length (0.43 mm, 1.27 mm, 1.0 mm, 1.56 mm and 1.28 mm, respectively). The difference, however, was statistically significant only when compared to that using Abdominal Circumference. Conclusion: We concluded that Transcerebellar diameter is the most accurate biometric measurement in both uncomplicated pregnancies and in complicated pregnancies with medical disorders such as Diabetes mellitus and hypertension especially when associated with fetal macrosomia or fetal intrauterine growth restriction and in structural abnormalities affecting organs other than cerebellum as the cerebellar growth is not affected by these circumstances.