Your boyfriend gets an A+ for creativity and an F for factual research.

No, TeenHealthFX has not found any research that has been done on breast cancer and the act of swallowing semen. To our knowledge and medically, there is nothing in semen that either causes or does not cause breast cancer. We are glad that you are questioning the accuracy of this. It is good not to believe everything you hear and question things that sound a little odd.

If you and your boyfriend are having sex it is important you follow safer sex guidelines. Remember to use a new condom every time you have intercourse and when you have penis-to-mouth contact to prevent STDs.