[Longitudinal studies on the physical development of low birth weight children. Growth dynamics and sexual dimorphism during the first year of life].

Longitudinal studies of physical development in the first year of life were carried out in the group of children born with low body weight. Results were compared with those obtained in the control group. The examined group consisted of 73 children born from single pregnancies in hospitals from families living in Wola district of Warsaw. Out of 73 children, 35 were born t term as small-for-date children (DW). Remaining 38 children were prematurely born (W). The control group (K) consisted of 40 children born in hospital at term, from single pregnancy, with body-weight at birth corresponding to foetal age (25-75 centiles). They came also from families living in Wola district. Analysis of physical development was based on the results of anthropometric measurements carried out at monthly intervals through the first year of life, considering required age tolerance, using standardized measuring methods and instruments. The principles of feeding, nursing, prophylaxis of rickets and iron deficiency as well as preventive vaccinations were the same for all children. Variability with age as well as monthly and yearly gains and the index of sexual dimorphism of the following parameters were analysed: body-weight, body-length, head and chest circumference thorax and head length, shoulders width, hip width. Longitudinal observation of these children through evaluation of growth increments made the analysis of the dynamics of somatic development possible. The analysis showed differences in physical development in the first year of life in children under examination. These differences concerned both the variability of separate traits with age, and the dynamics of development, development of sexual dimorphism index in relation to the control group. The differences ere also observed between the small-to-date and prematurely born children. Developmental differences ere noted among the children born with low body-weight dependent on the achieved foetal age at birth. No tendency in small-for-date infants to decrease the differences as compared to the control group was noted. This tendency was typical of the prematurely born children. The highest developmental rate was observed in prematurely born infants.(ABSTRACT TRUNCATED AT 400 WORDS)