Can a bone marrow transplant cause infertility?

YES: The highh doses of chemotherapy (and whole body radiation) used in bmt often causes infertility.

In many cases: Yes, in, many cases the chemotherapy and/or radiation will cause infertility. This will depend on the drugs and doses used and the gender of the patient.

In most cases: I agree with the other doctors but i will take it a bit further. Almost all bone marrow transplant patients are sterile, that is no eggs or sperm. These individuals will then need donor eggs or sperm to achieve a pregnancy with their partners (or as single parents). The very high does of chemo and radiation required for bmt are very toxic to gametes.