[The physical development of infants and young children. 4. Body mass--a longitudinal study].

As a result of a longitudinal study (performed 1979-1982) on the somatic development of 84 male and 91 female children from birth up to the third year of life, values of body mass expressed as distance values, increments, and growth velocity are presented. As compared to earlier investigations made in the G. D. R. and to studies from other countries differences of the dynamics of body mass development have been found: with the exception of the birth weight the body mass tends to be higher during the first six month of life in contrast to previous studies, whereas between the 9th to the 18th month of life lower values of body mass have been measured. Additional differences in the dynamics of body mass development between boys and girls are presented.