Survey on the Body Weight of Newborn Infants

Abstract

It seems that the mental and physical development of the children would be influenced by the growth at their birth.Therefore we investigated the relationship between the body weight of newborn babies and the conditions of their births, and also investigated the physiological derease of body weight with 873 newborn babies which were born from Janurly to December 1959, at a maternity hospital in Tokyo.Results were shown as follows:1. The body weight of the male infants were 3.162kg. and those of female were 3.101kg. All of them were greater than those of the average weight reported in our whole country.2. As for the relation between the period in mother's uterus and the body weight at birth, there was some difference between the male and the female.The body weight at birth of newborn babies being 40-42 weeks in mother's uterin was the greatest on both sex. The shorter the period in mother's uterus the smaller the body weight at birth.3. The relation between the body weight and their born order was as follows: In the case of the male, the body weight incresed in the order of first, second and then third, on the other hand, in female, second, first and then third.4. The relation between the body weight and the mother's age, showed that the body weight of the babies which were born by mothers of 30-31 years old were the greatest.5. The highest grade of the physiological decrease of body weight was shown by the infants with medium birth weight.6. The relation between the feeding way and physiological decrease of body weight was as follows:In the case of the breast-fed babies, the higher grade of decrease was seen in the babies of greater body weight. By mixed feeding, higher grade of decrease was seen by medium birth weight, and then bottle feeding babies showed generally smaller reduction.7. The greater the decrease, of physiological body weight the longer time was required for the recovery.