Paternity after irradiation for testicular cancer.

According to the Medical Birth Registry (MBR) of Norway, 69 of about 430 patients irradiated for testicular cancer (stage I + II) during 1966-1978 fathered at least one child after radiation therapy (median observation time 136 months, range 36-191 months). A total of 95 children were born. Between 10 and 122 months elapsed between discontinuation of irradiation and the birth of the first child born after radiation therapy. Though the total doses to the abdominal irradiation field were higher in patients irradiated by a linear accelerator (1971-1978), than in those treated by a betatron (1966-1970), the gonadal doses were generally lower in the former group due to better gonadal shielding. In the children, the sex ratio and the median weight and length at birth were comparable to those values seen in a control group from the MBR. No increased frequency of malformations was observed. It is concluded that modern radiation therapy techniques allow post-irradiation fathership in a significant number of patients, without increased risk of neonatal problems or malformations in the children.