INVESTIGATION on animal fetuses and clinical studies of postconception pelvic irradiation have demonstrated a damaging effect of radiation upon the development of the fetus.* This paper presents a report of investigations being made on the effects of the atomic explosion on fetuses of women who were in Nagasaki on Aug. 9, 1945.
COLLECTION OF DATA
A. Patient Selection.—This study was conducted in Nagasaki during the first half of 1951. On the basis of information obtained from the pregnancy records of the genetics program, lists were made of all women who, at the time of the explosion, were of childbearing age (for the purposes of this study, 17 to 50 years of age) and were residing in Nagasaki. A home investigation was done by trained personnel to determine if the mother had been pregnant at the time of the bombing. Conception was considered to have occurred two weeks after the