My wife is suffering from breast cancer and is on her treatment currently. Yesterday she had an emergency contraceptive pill. Is it safe?
Talk to her oncologist.
Yes.
From a radiation standpoint, yes. I don't think the contraceptive would interfere with chemotherapy, but I would ask her medical oncologist to be sure.
Contraceptive pills containing estrogen are controversial. Most breast cancers are estrogen and/or progesterone receptor positive. It is therefore prudent to avoid estrogen in any form.