If a man has a low sperm count as a side effect of taking a prescription medication, is there an increased possibility that the remaining sperm would be defective or more likely to create genetic or birth defects if conception were to occur? The drug in this case is Sulfasalazine. Kim
Sulfasalazine is typically used to treat inflammatory bowel disease (ulcerative colitis). As you know, Sulfasalazine treatment can lower sperm count; it can also affect sperm motility (movement) and morphology (shape).
One study of men with inflammatory bowel disease suggests that while there was no overall increase in birth defects in the offspring of men who had the disease, the risk of abnormality was higher in the smaller subgroup who were treated with Sulfasalazine. Unfortunately, we do not yet have a clear answer as to why this occurred. Was the outcome worse in this subset because their disease was more severe and required more intensive therapy? Or did the men who were treated with other medications gain some protection against birth defects as a result of those drugs?
We still have a lot to learn before our team can advise you with confidence. But there is hope. One study looking at the effects of a newer enteric-coated version of Sulfasalazine found it did not adversely affect sperm production.