Systemic dermatological treatment with relevance for male fertility.

The dermatologist employs systemic agents with likely gametotoxic side effects, including cytotoxic, immunosuppressive, immunomodulatory and biological agents. The impact of chemotherapy on male fertility depends on the treatment protocol as well as the pre-treatment spermatogenesis status. Sperm concentration starts to drop about 2 weeks after beginning chemotherapy and reaches a maximum after 2-3 months. About half show recovery after 12-36 months. One year after therapy is completed, a treated patient has no increased risk of fathering a malformed child. There are no reports of methotrexate patients fathering children with malformations, most likely because impaired fertility or embryogenesis arrest. Cryopreservation of male gametes should be recommended prior to cytotoxic treatment, since the likelihood of post-treatment fertility is unpredictable. The cryopreservation causes a loss of vital spermatozoa by 30-70% but does not influence the genetic information of gametes. Males treated with retinoids have no reproductive safety risk. Biologicals inhibiting TNF alpha show a positive effect on sperm function in vitro.