If surgery or chemotherapy is planned, breastfeeding (breast milk production) and breastfeeding should be stopped.
Breastfeeding should be discontinued if surgery is planned to reduce blood flow in the breast and make it smaller. Many chemotherapy drugs, especially cyclophosphamide and methotrexate, may be present in large amounts in breast milk and may cause harm to the nursing infant. Women receiving chemotherapy should not breastfeed.
Stopping breastfeeding does not improve the prognosis of the mother.
Breast cancer does not appear to harm the unborn baby.
Breast cancer cells do not appear to be passed from mother to unborn baby.
Pregnancy does not seem to affect the survival of women who have had breast cancer in the past.
For women with breast cancer, pregnancy does not appear to affect their survival. However, some doctors recommend that women try to have children 2 years after being treated for breast cancer so that any early recurrence of the cancer can be detected. This may influence a woman’s decision to become pregnant. If the mother has breast cancer, the fetus does not appear to be affected.