The short answer
Cancer treatments can lower a man's fertility or cause infertility by affecting sperm, hormones, or reproductive organs. The effect depends on the treatment, dose, age, and other factors, and it may be temporary or permanent. After treatment, men can ask their team about the chances of fertility returning and how long it may take.
A man's fertility depends on making and releasing healthy sperm and on hormones.
Chemotherapy, radiation to the pelvis or brain, hormone therapy, surgery, and stem cell transplant can affect fertility.
Some chemotherapy drugs, such as alkylating agents, carry a higher risk to sperm.
Changes may be temporary or permanent, depending on the treatment and the person.
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The full explanation.
What male fertility depends on
Fertility is the ability to produce children. According to the National Cancer Institute (NCI), a man's fertility depends on a working reproductive system that makes and releases healthy sperm, and an endocrine system that makes hormones. Cancer treatments can affect either of these, and the changes may be temporary or permanent.
What affects whether fertility changes
Whether your fertility is affected depends on the type of treatment, the dose and length of treatment, your age, the time since treatment, the type of cancer and whether it is near the reproductive organs, your fertility before treatment, and other health factors.
How treatments can affect fertility
NCI describes how different treatments may affect male fertility:
- Chemotherapy can harm sperm and the sperm-forming cells (germ cells). Some drugs, such as alkylating agents, carry a high risk. High doses or several drugs at once can raise the risk.
- Radiation therapy to the pelvis can affect sexual function and fertility, and radiation to the brain can affect glands that make the hormones fertility needs.
- Hormone therapy can lower sperm count.
- Surgery for prostate, testicular, penile, bladder, colon, and rectal cancers can affect the production or release of semen and sometimes cause retrograde ejaculation (a dry orgasm).
- Stem cell transplant often follows high-dose chemotherapy, radiation, or both, which can damage sperm and sperm-forming cells.
- Targeted therapy effects are still being studied; some drugs called tyrosine kinase inhibitors may lower sperm and hormone production.
The cancer itself can matter
Some cancers affect fertility even before treatment. NCI notes that men with testicular cancer, prostate cancer, and other germ cell cancers are sometimes found to have poor semen quality and low sperm count at diagnosis. Men with Hodgkin lymphoma may have low or no sperm in the semen. Cancers common in children and young adults, such as lymphoma, leukemia, and central nervous system tumors, are also linked with fertility problems.
After treatment
Changes to fertility may be temporary or permanent. NCI suggests asking your doctor after treatment:
- What are the chances that people who have this treatment are fertile afterward?
- How long might it take for my fertility to return?
- Should birth control be used after treatment, and if so, for how long?
Even when treatment lowers fertility, pregnancy can still be possible, and some treatments can be harmful to a pregnancy, so your doctor may advise condoms or other birth control for a time.
Getting support
A growing number of hospitals have social workers and patient navigator programs that help with fertility-related resources and cost. Support groups and counseling can also help. Your care team is the best guide to what your specific treatment may mean for your fertility.
Words to know
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Common questions
▸How do cancer treatments affect male fertility?
They can harm the reproductive organs, the sperm-forming cells, or the endocrine glands that make hormones. Depending on the treatment, this can lower sperm count or cause infertility, which may be temporary or permanent.
▸Which treatments carry more risk?
Some chemotherapy drugs, such as alkylating agents, carry a high risk. Radiation to the pelvis, brain, or reproductive organs, hormone therapy, some surgeries, and stem cell transplant can also affect fertility.
▸Can men have children after treatment?
Sometimes fertility returns after treatment and sometimes it does not — it depends on the treatment and the person. After treatment, ask your doctor about the chances of being fertile and how long it might take to return.
▸Does the cancer itself affect fertility?
It can. Men with testicular cancer, prostate cancer, and other germ cell cancers are sometimes found to have low sperm count at diagnosis, and men with Hodgkin lymphoma may have low or absent sperm in the semen.
▸Is birth control needed after treatment?
Your doctor may advise birth control during and sometimes after treatment. Ask whether it is recommended for you and for how long.
Questions to ask your doctor
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