Introduction: The estimates of age based on measurements of Head Circumference can be used as an alternative in pregnancy dating. These additional measurements taken provide a more ‘universal view’ of the foetal development than can be afforded by any single measurement. In the present study Bi-parietal diameter [BPD] & Head Circumference [HC] were measured to study the correlation and significance of this parameter with LNMP in estimating the foetal gestational age [FGA].