What Chemotherapy Can Do
Fertility is temporarily affected by chemotherapy - which happens to do a very good job at killing testicular cancer - by killing germ cells. Chemotherapy affects sperm growth because sperm are generated by germ cells.
Chemotherapy usually results in azoospermia (the absence of sperm) during therapy. In most cases, even though sperm is absent during therapy, it will increase within two to three years following the end of treatments, with about 50% of men achieving normal levels once again.
However, many men end up with very low sperm counts even after five years from the end of treatment. The more chemo received, the less likely fertility will return. Since there is such a high probability of infertility for an indefinite period of time after chemotherapy, men are encouraged to bank sperm prior to treatments.
How Radiation Affects Male Fertility
Seminoma (germ cell testicular cancer) has been treated over the years with radiation. Although it has been thought that this kind of treatment will render a man sterile, there is no medical evidence that would occur. Of course, high levels of radiation aimed directly at the testicle will sterilize a man, but this type of treatment is only used in cases of carcinoma-in-situ, where the cancerous cells are all in one place.
If high potency radiation is necessary, then banking sperm is necessary as well. There may be a temporary reduction in sperm with regular radiation therapy, no permanent damage normally ensues.
Some oncologists recommend waiting one or two years to try conceiving while others say six months is sufficient. It is a good idea to bank sperm before the beginning of treatment just to be sure.