A study on the factors related to birth weight in "Buraku" (socio-economically discriminated) areas in Japan

A questionnaire study on factors related to birth weight was carried out in a "Buraku" area and control area from 1975 to 1984. Altogether, 111 births were covered in the "Buraku" area, and 309 in the control area. The incidence of low birth weight was found to be significantly higher in the "Buraku" area than in the control area. Factors related to the high incidence of low birth weight were observed more frequently in the "Buraku" area than in the control area. Among these factors, the duration of gestation, the number of days-off before delivery, and the mother's physical structure and smoking habits were found to be strongly related to the incidence of low birth weight. Such factors as the number of days-off before delivery and mother's smoking habits were also found to have a high relation to socio-economical factors: These results demonstrate that the incidence of low birth weight is significantly higher in the "Buraku" area than in the control area, and that this phenomenon is brought about by poor health of the mother and socio-economical factors.