HIROSHIMA AFTERMATH REGISTRATION

Among the 18,876 children re-examined at that age, 378 had one or more major birth defect (2.00%), compared with 0.97% within two weeks of birth. Since many birth defects, especially congenital heart disease, are not detected in the neonatal period, repeat examinations were conducted at age eight to ten months. These abnormalities accounted for 445 of the 594 (75%) malformed infants in Table 3. The most common defects seen at birth were anencephaly, cleft palate, cleft lip with or without cleft palate, club foot, polydactyly (additional finger or toe), and syndactyly (fusion of two or more fingers or toes). No untoward outcome showed any relation to parental radiation dose or exposure. The incidence of major birth defects (594 cases or 0.91%) among the 65,431 registered pregnancy terminations for which parents were not biologically related accords well with a large series of contemporary Japanese births at the Tokyo Red Cross Maternity Hospital, where radiation exposure was not involved and overall malformation frequency was 0.92%. Newborn frequencies of untoward pregnancy outcomes, stillbirths, and malformations are shown in Tables 1, 2, and 3 according to parental dose or exposure. Physical examination of newborns during the first two weeks after birth provided information on birth weight, prematurity, sex ratio, neonatal deaths, and major birth defects.

HIROSHIMA AFTERMATH REGISTRATION

This supplementary ration registration process enabled the identification of more than 90% of all pregnancies and the subsequent examination of birth outcomes.

When surveillance began, certain dietary staples were rationed in Japan, but ration regulations made special provision for women who were at least 20 weeks pregnant. During that period, 76,626 newborn infants were examined by ABCC physicians. Monitoring of nearly all pregnancies in Hiroshima and Nagasaki began in 1948 and continued for six years. No statistically significant increase in major birth defects or other untoward pregnancy outcomes was seen among children of survivors.

Hiroshima aftermath