A procedure used to help keep a person fertile by preventing damage to reproductive organs during radiation therapy. A protective shield is placed on the outside of the body to cover the area of the gonads (the testicles or ovaries) and other parts of the reproductive system during radiation therapy. For males, this would also include the prostate and penis. For females, it would also include the fallopian tubes, uterus, cervix, and vagina. Gonadal shielding is a type of fertility preservation.