Risks of fetus irradiation in X-ray and radioisotope examinations in early stages of pregnancy

Radiation burden is discussed of the fetus in pregnancy. During organogenesis the fetus is not capable of repairs; irradiation causes growth inhibition and malformations. In the last trimestre, irradiation causes disturbances in the somatic growth, leukemia is found in greater incidence in newly-borns. Doses are tabulated from commonest X-ray examinations and the applications of radiopharmaceuticals. The said doses are only valid for the first five weeks of pregnancy; when the thyroid starts functioning, the total dose retained in the thyroid after the application of radiopharmaceuticals may be higher. (H.S.)