Abstract
Frequency of prenatal X-ray examination in 1, 701 parturient women was surveyed in 19 Japanese hospitals in 1974. Of 1, 701 women, 470 or 27.6% have received maternal X-ray examination during the pregnant period. There is no significant difference in frequency of prenatal X-rays between in the primipara and multipara. Chest examination was frequent in the 3rd to 6th month of gestation, while a pelvimetric study was performed mainly after the 10th month. About 82% of the fetal dose was contributed from a prenatal pelvimetric study. The fetus receives averagedly 202 mrad of radiation from the prenatal X-ray examinations. It is calculated that about 6.3 leukemias may be induced yearly by maternal X-ray. This corresponds to about 1% of leukemias in the same generation.
