[13-cis-Retinoic acid and spermatogenesis. Spermatological and impulse cytophotometric studies].

Twenty male volunteers with severe acne conglobata were treated orally over a period of 12 weeks with 1 mg isotretinoin (13-cis-retinoic acid) per kilogram body weight. Before and after therapy, as well as 12 weeks after the end of therapy, the semen was examined spermatologically and the spermatozoa DNS determined by impulse cytophotometry. The sperm density remained unchanged in the otherwise healthy patients, whereas patients with previous gonadal defects (unilateral cryptorchism, hypogonadism, varicocele) the sperm count rose significantly (P less than 0.05) at the end of therapy; 3 months later a reverse trend in the sperm density was noted. The percentage of morphologically normal spermatozoa was slightly reduced at the end of therapy; 12 weeks after completion of therapy it was significantly reduced (P less than 0.05). This could, however, be due to the short elimination half-life of 13-cis retinoic acid and have nothing to do with the drug. On impulse cytophotometry the spermatozoa DNS showed no significant changes. According to the results of the cytophotometric examination, contraceptive measures for men during treatment with 13-cis-retinoic-acid need not be made obligatory.