No, contrary to the above post it is NOT a 50/50 chance. 99.5% of all males with CF are infertile. Meaning that they can not have children the "traditional" way. Your boyfriend can be tested by ejaculating into a cup and having hte results run by a lab. There is a 99.5% chance that there will be no sperm in the results. That either means he has no Vas Deferns (a tube leading from the testicles to ejacultaion) or it is obstructed (one are the other are very common in CF males). But don't loose hope, there are always "non-traditional" methods of geting pregnant. Such as In-vetro, or ICSI (intro cytoplasmic sperm injection).