Introduction. Transverse cerebellar diameter (TCD) measurement is very accurate in assessment of gestational age especially in cases where the LMPs are not exactly known. Normally value of the transverse cerebellar diameter in mm is considered roughly equivalent to the gestational age in week (particularly between the 14–20 weeks of gestation). It is of utmost importance to identify the fetal growth restriction during the antenatal period because it involves perinatal mortality and morbidity. TCD is a useful parameter for assessing fetal growth retardation.  The purpose of my study is to evaluate the accurate measurement of transverse cerebellar diameter as against the conventional parameters in assessment of gestational age in normal pregnant women between 16 to 38 weeks.

Material and Methods:.It was a prospective cross–sectional  study and All data were collected from 100 antenatal women of gestational age 16–40 weeks referred to Department of Radio diagnosis, Father Muller Medical College and Hospital for routine antenatal scans from May 2018 to October 2018 based on inclusion and exclusion criteria.

Results: In this study 100 cases were studied. Age distribution of normal pregnancies was ranged from: 18 to 35 years. 63 cases were multigravida and 37 were primigravida. In 95 cases the estimated gestational age predicted by measuring BPD, HC, AC and FL was also closely correlated with gestational age estimated from transverse cerebellar diameter measurements with a p value of 0.001. In 5 cases it was poorly correlating. We found good curvilinear relationship between the TCD and gestational age (R²=0.956) and (P=0.00012).

Conclusion: So our study shows that the TCD in the estimation of gestational age is consistently correlating with gestational age