CONTINUOUS ORAL LOW-DOSAGE CYPROTERONE-ACETATE FOR FERTILITY REGULATION IN MALE - TREND ANALYSIS IN 15 VOLUNTEERS

The effects of 10 or 20 mg cyproterone acetate (CPA) daily over 26 wk were studied in 15 healthy young males. Control periods of 18 and 16 wk, respectively, preceded and followed the phase of CPA medication. The salient observations under treatment were: a decrease in sperm density and in normal-shaped sperm with conversely an increase of pathological and immature forms, an increase in dead spermatozoa, a relative reduction of motile spermatozoa, a distinct drop in the speed of spermatozoa and a distinct decrease in the ability of the spermatozoa to migrate through the cervical mucus of ovulation quality in vitro. Androgen levels (mainly testosterone) in blood plasma dropped significantly to about 40% of the basal values, without concurrent effects on sexual behavior; no changes in plasma LH [luteinizing hormone] and FSH [follicle stimulating hormone] were observed; alkaline phosphatase values in seminal plasma were considerably elevated during treatment; no changes in fructose and sialic acid levels in seminal plasma were seen. CPA also increased significantly the cortisol-binding capacity of transcortin. A distinct inhibitory influence of low-dosage CPA on several parameters of male fertility is demonstrated. These reversible effects indicate that low doses of CPA might be used for fertility control in the male.