Abstract
In the previous report the differences in the intrauterine growth curves between infants in A. private clinic and those in O. public hospital in Naha were recognized. The aim of this study is to investigate these differences more exactly for the periods 1967-69 and 1972-74, by computing the mean and standard deviation of the birth weight, by sex, parity (primiparous and multiparous groups) and gestational age in weeks (35-43 weeks). The gestational ages were calculated to the nearest week (for example 227-283 days as 40 weeks). Generally the mean birth weights of infants in A. clinic are about 50-60 grams higher than those of O. hospital. These differences are statistically significant, especially between 38 and 41 gestational weeks. Some possible contributing factors causing these differences are discussed.
We concluded that this phenomenon was primarily due to the differences in the socioeconomic classes of the mothers giving birth in the two obstetric establishments, although we could not identify any contributor among the biological or sociobiological factors such as physical status, health conditions, maternal nutrition and pregnancy health control of the mother.
