One daily dose of either 5 mg or 10 mg cyproterone acetate (CA) was administered to 2 groups of 4 fertile men for 6 months. The medication was preceded by a 3 months placebo period and followed by a recovery phase of 5 to 8 months. During CA-treatment the sperm count/ml decreased and the percentage of abnormal spermatozoa increased slightly (0.001 < P < 0.05). Sperm penetration assessed by the Kremer test did not show any decrease during treatment. Serum levels of testosterone and FSH decreased, but those of LH remained unchanged during treatment. Two pregnancies occurred after 1¾ and 5½ months of CA-treatment. The serum-CA concentration in these 2 volonteers did not differ from that of the remainder. Three subjects who began the study were withdrawn because of depressive mood changes (2) and weakness combined with dizziness (1). Data from these subjects were not included. The results indicate that daily doses of 5 mg and 10 mg of cyproterone acetate are not effective as a male contraceptive.

The effect of steroid hormones on the ultrastructure of meiosis in the human male was analyzed by three dimensional reconstruction of 460 chromosomes from 7 early pachytene, 2 mid pachytene and 1 late pachytene spermatocyte nuclei. The testicular biopsy was obtained from a volunteer who had been treated with d-norgestrel 500 mcg per day orally and testosterone enanthate 200 mg every 4 weeks intramuscularly for 8 months and who was still under treatment. The volunteer had 17 months previously been treated with cyproterone acetate 5 mg per day orally for 6 months.The analysis of the synaptonemal complex, the number and distribution of recombination nodules and the general morphology of the bivalents did not reveal any damage by the hormonal treatment. In addition to the morphological features of human pachytene spermatocytes described in literature, bridgelike structures uniting the lateral components of the synaptonemal complex was found.

Abstract. Two groups of six men took levo-norgestrel (250 or 500 μg daily) by mouth and testosterone oenanthate (200 mg monthly, intramuscurlarly) for six months. A three months placebo period preceded the medication which was followed by a recovery phase of 6–10 months. Two volunteers withdrew due to side effects. The five men taking the low doses of levo-norgestrel (250 μg) exhibited a reduction in sperm count, but not to azoospermia. The high dose of levo-norgestrel (500 μg) was more effective, sperm count was reduced to < 6 × 106/ ml in 3 of 5 volunteers and to < 17 × 106/ml in the remainder. s-Testosterone, LH and FSH were decreased by the treatment. The men had no toxicological side effects or changes in libido and potency. During the recovery period sperm counts, sperm morphology, s-testosterone, LH and FSH returned to normal levels.