Some breast cancer treatments are not recommended for women who are pregnant when diagnosed with breast cancer. Some treatments can also affect a woman’s ability to have children in future.
Treatment for breast cancer during pregnancy
If a woman is pregnant when she is diagnosed with breast cancer:
- it’s possible to have breast surgery with only a slight risk of miscarriage; the risk of miscarriage is lower after the first trimester
- radiotherapy is not recommended because it may harm the unborn baby; radiotherapy can be given after the baby is born
- chemotherapy is not recommended during the first trimester because it may harm the unborn baby; chemotherapy is often given during the second and third trimesters, when the risk of harm is lower
- hormonal therapy and trastuzumab (Herceptin®) are not recommended.
Pregnancy during treatment for breast cancer
It’s recommended that women do not become pregnant during treatment for breast cancer. Treatments such as chemotherapy and radiotherapy can harm the unborn baby.
Women should use contraception if it’s possible that they could become pregnant during treatment, even if periods become irregular or stop during treatment.
Effects of breast cancer treatment on fertility
Some treatments for breast cancer can affect a woman’s fertility. Once treatment has finished there’s no reliable test to find out if a woman will be able to fall pregnant in future.
Women who were planning to have children before their breast cancer diagnosis should speak to their oncologist before starting treatment for breast cancer. It may be possible to see a fertility specialist to discuss the available options.