[Data and comments on the general validity of the weight limit of 2500 g for low-birth-weight infants]

The authors describe the role of maternal body weight, duration of pregnancy and sex of newborn in the intrauterine growth of the fetus, more exactly in the development of birth weight. In this context they dealt with the validity of the 2500 g upper limit of low-birth-weight-infants in ethnically different populations. From the findings of their studies they draw the conclusion that the weight limit of 2500 g cannot be regarded as valid for all the populations at the statement of the proportion of low-weight births. In the authors view the question of the upper limit of low-weight newborns should be revised. At the statement of the weight limit a differentiation is necessary taking into consideration the constitutional difference in the populations as well as the average birth weight of the newborn and the sex. Authors find it permissible to use the weight value of 2500 g in comparative studies only in case of some populations with identical constitutional characteristics.