Understand · Sex + Relationships
The short answer on sex during breast cancer treatment
Sex during breast cancer treatment is usually safe, but ask your team. You can't catch cancer through sex, and sex doesn't make it worse or bring it back. Chemo can harm a pregnancy, so effective birth control is usually advised even if your periods stop. Chemo can also lower your defenses against infection, and some teams suggest condoms or dental dams for a short time after each dose.
What to know about sex during breast cancer treatment
- Cancer is not contagious. Sex cannot spread it or make it worse.
- Birth control matters. Missed periods do not mean you cannot get pregnant.
- Infections are more likely. Chemo can lower your defenses.
- Advice on condoms varies. Ask your own team.
Part of Babette's series on sex after breast cancer.
Is it safe to have sex during breast cancer treatment?
Usually, but ask your team, because some situations, such as very low blood counts, can change the answer. A UK guide by sex therapists and cancer nurses says you can't catch cancer or pass it on through sex, and that sex doesn't make cancer worse or bring it back. It also notes that it's very common not to feel like it during treatment.
Do you need birth control during chemotherapy for breast cancer?
The American Cancer Society (ACS) says many chemo drugs can harm a pregnancy, so effective birth control is usually advised, and that periods stopping doesn't mean you can't get pregnant. Ask how long to keep using it after treatment, and talk about fertility before chemo starts if you may want children. Ask which kinds of birth control are safe for you, since some contain hormones.
Should you use condoms after chemotherapy?
Some teams advise condoms or dental dams for a short time after chemo, in case traces of the drug are in body fluids. The UK guide notes that advice varies from team to team, from no special precautions to the whole course of treatment, so ask yours.
Can chemotherapy cause vaginal infections?
Yes. The ACS says chemo can weaken your defenses, making yeast infections more likely, with itching, a thick white discharge and burning during sex. It says genital herpes or warts you've had before can come back. Practice safer sex, and don't move anything that has been near the anus to the vagina or urethra.
When to call your care team about a sexual side effect
- Itching, burning or a thick white discharge, which can mean a yeast infection
- Sores, blisters or warts on or around the genitals
- Bleeding after sex that's more than light spotting, or keeps happening
- Pain during sex that doesn't ease with lubricant
None of these needs to wait for your next routine visit.
If it feels like an emergency, call 911.
Questions to ask your care team about sex during treatment
- Is it safe for me to have sex during treatment? Are there times I should avoid it?
- What kind of birth control is safe for me, and for how long?
- Do I need condoms or dental dams after chemo, and for how long?
- What signs of infection should I call you about?
More from Babette on sex after breast cancer
- Why Does Breast Cancer Treatment Change Your Sex Life?
- What Helps Vaginal Dryness After Breast Cancer?
- Is Vaginal Estrogen Safe After Breast Cancer?
- Why Does Sex Hurt After Breast Cancer?
- Where Did My Sex Drive Go After Breast Cancer?
- How Do You Talk About Sex After Breast Cancer?
- Sex and Intimacy After Breast Cancer, by founder Jasmine Jones
Sources: American Cancer Society, Managing Sexual Side Effects as a Woman with Cancer (accessed October 2026); American Cancer Society, How Hormone Therapy, Chemo, and Immunotherapy Can Affect Sex for Women (revised April 15, 2025); Brandenburg, Grover and Quinn, Intimacy & Sexuality for Cancer Patients and their Partners (UK, 2010). This article is general information, written in Babette's own words, and is not a substitute for advice from your care team.
