A prospective study of 9000 single live born babies with known gestation was conducted during the period January 1967 to June 1970 with a view to find out incidence of prematurity, relationship between gestation and birth weight and other anthropometric measurements. Feeding and respiratory problems along with mortality rate was studied for accurate appraisal of the newborns. The incidence of prematurity on the basis of 2000 G. and below was 11.27% as compared to 48.16% when based on the international standard of 2500 G. Prematurity in the gestational age group of 37 weeks or less was only 10.9% which was further reduced to 9.07% when gestation below 37 weeks and weight below 2500 G. were combined. Majority of the babies below 2500 G. (81.17%) had gestation period more than 37 weeks. In the same weight group all the anthropometric measurements were higher in babies with longer gestation. A higher mortality was observed amongst the same group of babies with low birth weight and shorter gestation. Prognosis improved with increase in weight and in the length of gestation. Physiological response was more mature in the babies with longer gestation in the same weight group. On the basis of the above observations the authors suggest that for correct and accurate appraisal of the newborn, gestation, birth weight with other anthropometric measurements, functional maturity, different clinical problems peculiar to newborns and mortality should be studied in combination and where this is not possible, babies below 2000 G. with gestation less than 37 weeks should be labelled 'Premature Low Birth Weight Infants' and babies between 2000-2500 G. with gestation more than 37 weeks be labelled 'Full Term Low Birth Weight Infants'. © 1973 Dr. K C Chaudhuri Foundation.