Abstract
The mean dose to the fetus and fetal head, together with the doses to the fetal gonads and maternal gonads, were about 107, 56, 131 and 136 mrad, respectively, for an obstetric prone oblique examination of the abdomen, using a rare-earth screen-film combination. The doses were derived by measuring skin doses on a series of women in late pregnancy undergoing the above examination and by using measured depth-dose information. The position of the fetus relative to the maternal skin surface was determined by ultrasonic scanning. [An increased cancer risk associated with ante-natal radiography was discussed].