Testosterone Undecanoate Maintains Spermatogenic Suppression Induced by Cyproterone Acetate Plus Testosterone Undecanoate in Normal Men

Testosterone undecanoate maintains spermatogenic suppression induced by cyproterone acetate plus testosterone undecanoate in normal men.

In this study we evaluated whether testosterone undecanoate (TU), alone or combined with low dose cyproterone acetate (CPA), can maintain spermatogenic suppression induced by higher doses of CPA plus TU. Twenty-four men received for 12 wk 20 mg/d CPA plus 1000 mg/6 wk TU and then 1000 mg/8 wk TU plus 20 mg/d CPA (n = 8), 2 mg/d CPA (n = 8), or plus placebo (n = 8) for 32 wk. Blood samples, phys...

Long-acting testosterone undecanoate for parenteral testosterone therapy

Low-dose human chorionic gonadotropin maintains intratesticular testosterone in normal men with testosterone-induced gonadotropin suppression.

In previous studies of testicular biopsy tissue from healthy men, intratesticular testosterone (ITT) has been shown to be much higher than serum testosterone (T), suggesting that high ITT is needed relative to serum T for normal spermatogenesis in men. However, the quantitative relationship between ITT and spermatogenesis is not known. To begin to address this issue experimentally, we determine...

Suppression of spermatogenesis by testosterone undecanoate-loaded injectable in situ-forming implants in adult male rats

We have investigated the feasibility of administration of testosterone undecanoate (TU)-loaded injectable in situ-forming implant (ISFI) for contraception in adult male Sprague-Dawley rats. Male rats were treated with vehicle, TU-loaded ISFIs (540, 270 and 135 mg TU kg-1 ) or TU injections (45 mg TU kg-1 every 30 days) for 120 days. Fertility tests served for determining infertility or restorat...

Male hormonal contraception: suppression of spermatogenesis by injectable testosterone undecanoate alone or with levonorgestrel implants in chinese men.

Monthly injections of testosterone undecanoate (TU) act as a male contraceptive by reversibly suppressing spermatogenesis to azoospermia or severe oligoazoospermia in 95% of Chinese men. In 5% of Chinese men, however, monthly TU administered alone fails to suppress spermatogenesis into contraceptive ranges, or sperm "rebound," leading to occurrences of pregnancy during treatment. Since combinat...