Frequently asked questions

Can sex cause cancer?

Many patients and their partners worry that cancer is catching. But, a cancer cell from one person’s body simply cannot move in during sex, take root, and grow in someone else. And for most cancers, there is no link between a person’s sex life and cancer risk or having cancer come back after treatment.

There are a few viruses passed from one person to another through sex that can cause some kinds of cancer, like cancer of the cervix, vagina, penis, anus, and oral cavity, and Kaposi sarcoma. Hepatitis B and hepatitis C viruses can be passed to others during sex, and can raise the risk for liver cancer. The virus that causes mono (the “kissing disease”) seems to raise the risk of certain cancers, too.

Still, these cancers are not caused by sex itself. They are caused by viruses that can be picked up during sex with someone who has the virus. Most people with these viruses never get cancer. For more information, call us at 1-800-227-2345 and ask for Infectious Agents and Cancer.

Can you get AIDS from having sex?

Yes. The virus that causes AIDS is called HIV (the human immunodeficiency virus). It can be passed to others when semen, vaginal fluid, or blood from an infected person gets into someone else’s body. This can happen during oral, vaginal, or anal sex. This virus is passed on in 3 ways:

• Unprotected sex (sex without a condom) with an infected person
• Sharing an infected person’s needle or equipment when injecting drugs
• From a mother to her baby during pregnancy or breast-feeding

The only way to find out if a person has HIV is for them to take an HIV test. Unless you are sure that neither you nor your sex partner has the virus, you should practice safer sex. For more on safer sex, see “Other problems from chemo that may affect your sex life” in the section called “Chemotherapy (chemo) and sex.” For more on HIV, you can call and get our information HIV Infection and AIDS.

Can having sex during chemo or radiation hurt your partner?

A few chemo drugs can come out in small amounts in vaginal fluids. You may want to use condoms while you are getting chemo and for about 2 weeks afterward. Having sex with you will not expose your partner to radiation unless you have an implant that gives off radiation. Talk to your doctor or nurse about any questions or concerns.

When should a person with cancer not have sex?

Ask your doctor if sex would cause a problem any time during or after treatment. Here are some things to think about:

• After surgery, sex can cause bleeding or pull the stitches. Sex may also raise your chance of an infection. Ask your surgeon when it’s safe to try sex again.
• Some types of cancer, like cancer of the cervix or bladder, may cause bleeding in the genital area. If bleeding gets worse after sex, talk to your doctor about it.
• During cancer treatment with chemo or radiation, your immune system may not work very well and you can get serious infections. Ask your doctor if sex is too risky. Most doctors say that if you are well enough to be out in public, you are well enough to have sex.
• Some of the bacteria that can start an infection in the bladder or genital area can be washed away by emptying the bladder just after sex. Some doctors also suggest washing the genital area before sex and drinking extra fluids. If you have urinary tract infections often, your doctor may give you antibiotics to take after sex to help prevent infection.
• If you notice any sores, bumps, or warts on your partner’s genitals, or a white or greenish-gray fluid (other than semen) in the opening at the tip of the penis, find out what’s going on before you decide if it’s safe for you to have sex with this person.

What about sex and advanced cancer or at the end of life?

A very ill person is not often seen as a sexual person. But everyone has sexual feelings. Touching, sharing, and closeness are always important, even at the end of life.

When cancer is far advanced, a person’s needs for affection, sharing of feelings, and touch may become even stronger. You may need to remind your partner how important physical closeness is, even when sex might be too much.

Do you have other questions?

You might have many questions that haven’t been addressed here. Don’t be afraid or embarrassed to ask your doctor or other members of your health care team. Write them down now so you’ll remember to ask them at your next visit.

Sometimes your doctor might say things you don’t understand. It’s OK to speak up. Let the doctor know what didn’t make sense to you. Ask the doctor to try again to tell you what you need to know. If you still have trouble, a nurse or social worker can often help with questions.