Effects of Cancer Treatment on Fertility

When your child has cancer, it can be hard to think beyond the next few days or months. Yet because today's treatments are increasingly effective — the majority of children with childhood cancers survive, thanks to medical breakthroughs — it's important to understand how they could affect your child's fertility.

While some treatments have little to no effect on reproductive health, others are likely to damage the testes or ovaries, resulting in temporary or permanent infertility. Your doctor can tell you if there's a chance that treatment might affect the reproductive system.

Once armed with this knowledge, you and your child can consider what preventive measures (like sperm banking or egg preservation) to take before or after cancer treatment to help improve your child's ability to start a family later in life.

Risks of Treatment

Chemotherapy, radiation, and surgery all can have lasting effects on reproductive health. Your child's risk depends on the diagnosis, the type of treatment, and the dose of medicine — but even your doctor can't predict with 100% certainty what the lasting effects will be.

In general:

Some chemotherapy drugs are more likely to lead to infertility than others. The high-risk drugs most likely to affect reproductive organs are cyclophosphamide (known commercially as Cytoxan), lomustine, ifosfamide, procarbazine, busulfan, and melphalan. Others, like vincristine and methotrexate, are typically less likely to harm fertility. Some of these drugs also may interrupt menstruation in girls and/or cause early menopause.

Radiation treatments can damage testes or ovaries. If radiation is focused on or near the pelvic area, abdomen, spine, and/or the whole body, it may cause damage to sperm or eggs. Also, radiation to the abdomen, pelvic area, or entire body may affect a girl's uterine function and cause difficulty in carrying a baby to full term. It also can interrupt menstruation in girls or reduce sperm count and motility in boys — these conditions may be permanent or may reverse after the treatment. Kids who have radiation to certain areas of the brain also may have their fertility affected.

If the cancer involves the reproductive organs, surgery might be recommended and doctors might need to remove part of the reproductive organs to remove the cancer.

Sperm and Egg Preservation Options

If your child's treatment carries a high risk of infertility, here are some options to consider.

Boys

For boys who have gone through puberty, sperm banking or "cryopreservation" is a common, non-invasive option to consider. Sperm are collected and frozen for storage in a specialized facility. Some hospitals have sperm bank programs, but you may have to go to a clinic that specializes in sperm banking.

For younger teens and boys who have not yet hit puberty, a more experimental procedure called "sperm aspiration" may be possible. This process removes immature sperm cells for later use in in vitro fertilization (sperm are used to fertilize an egg outside of the uterus, then the fertilized embryo is transferred to the uterus).

It also may be possible to preserve sperm by freezing testicular tissue. This is still experimental and its effectiveness hasn't been determined. Your doctor may advise against it because of the risk that cancer cells could be reintroduced when the tissue is grafted back into your son's body.

Boys who have delays in puberty or growth delays due to chemotherapy and/or radiation should see an endocrinologist to discuss treatment options. For boys who collect sperm for preservation after having chemotherapy, there is a potential risk of damage to the genes in the sperm. If you have questions, make sure to ask your doctor.

Girls

Embryo freezing — in which eggs are harvested from the ovaries, fertilized in a lab, and then frozen and stored — is more widely available and has a higher rate of success. However, since it requires mature eggs, this method only works for girls who have gone through puberty. It's less commonly used in pubescent girls than adult women (because it requires sperm from a partner), but it is possible to user donor sperm to fertilize the eggs. Since this method requires a period of ovarian stimulation, it is not ideal for girls who need to start treatment as soon as possible. Therefore, many girls are not able to have eggs harvested.

If embryo freezing is not a possible option for the girl, unfertilized eggs (after puberty) can be frozen and preserved for later in vitro fertilization (IVF) and implantation. Pregnancy is possible through this method, though success rates are lower than with traditional IVF.

Depending on the specifics of a girl's condition, it may be possible to freeze ovarian tissue (before or after puberty). However, these are experimental processes — not all hospitals or clinics have the technology and success rates vary. In some cases, your doctor may recommend against preserving ovarian tissue because of the risk of reintroducing cancer cells later on.

Depending on the type and target area of treatment, it may be possible to shield the ovaries from damage or even move them out of the path of radiation (called transposition).

What to Ask the Doctor

When thinking through the options above, be sure to get all the facts from your care team. It might be helpful to see a fertility specialist about which option (if any) would be best for your child.

Some questions to ask:

• Is this treatment likely to damage my child's reproductive organs? If so, what areas may be affected and how will this impact fertility?
• What are the chances this treatment will cause my daughter to experience an early menopause? Can the treatment affect some organs (like the lungs or heart) in a way that will make it hard for her to carry a pregnancy to term?
• Will this treatment have any affect on my son's reproductive health? If damage to sperm is likely, will the damage be temporary or permanent?
• Will this treatment have any effect on development through puberty?
• Are there ways to prevent infertility before we start treatment? Will any of these interfere with how well the cancer treatment works?
• What proactive measures, like sperm banking or egg preservation, are possible for my child? Are any experimental options available?
• After treatment, how will we know if my child's fertility has been affected?

If infertility is a possibility, it's important to know about other options for the future, including adoption or surrogacy. A surrogate mother carries a child to full term for a woman who is not able to do so herself, for health reasons or due to infertility. The surrogate mother may carry a child who is her genetic offspring or may be implanted with an infertile couple's embryo via in vitro fertilization.

Emotional Effects

As you explore the options, it's important to share as much as you can with your child.

This probably won't be easy — sexuality and reproduction are often difficult subjects for parents and kids to discuss, and the risk of infertility carries complex emotions that can be hard for a child to process. Even in the very young, the concept of infertility can be powerful and intense.

Kids can have a deep sense of loss, or feel less feminine or masculine if faced with fertility problems — especially adolescents, for whom sexuality and reproduction are important parts of their developing identity.

Here are some ways to help your child cope with these potential changes:

Keep talking. An open discussion with your son or daughter will help you plan for treatment and know what to expect afterward. It's also important to let your child know that he or she is not alone, and that many teens who were told that their treatments would likely lead to infertility go on to have children; others go on to become parents through adoption, surrogacy, or other methods. Planning for the future can help your son or daughter stay positive and concentrate on getting well.

Seek support. The hospital or clinic may have a support group or counselor who can help work through the complex feelings your child is bound to experience.

Keep hopes realistic. Be open and honest about the risk of infertility, the success rates of fertility preservation options, and any possible risks or complications. Be sure you and your child understand that nothing is guaranteed. Offer reassurances that your child is still the same person, no matter what happens long-term. And remember, even if unable to physically conceive, your child can still become a parent one day.