Page ST et al. (2006) Testosterone gel combined with depomedroxyprogesterone acetate is an effective male hormonal contraceptive regimen and is not enhanced by the addition of a GnRH antagonist. J Clin Endocrinol Metab [doi:10.1210/jc.2006-1411]

Administration of exogenous androgens and progestins suppress pituitary secretion of sex hormones and inhibit spermatogenesis, but only injectable or implantable testosterone had previously shown efficacy. Page and colleagues have now demonstrated that transdermal testosterone gel plus depomedroxyprogesterone acetate (DMPA, a progestin) induced severe oligospermia in 80–90% of treated men; they also confirmed that acyline (a gonadotropin-releasing-hormone antagonist that directly suppresses pituitary sex hormones) did not improve the efficacy or rapidity of spermatogenesis suppression achieved by testosterone gel plus DMPA.

Their open-label study involved 44 men aged 18–55 years with normal spermatogenesis, who were randomly allocated to 24 weeks of treatment (100 mg of 1% testosterone gel self-applied daily, plus 300 mg intramuscular DMPA once every 3 months, with or without 12 weeks of 300 µg/kg subcutaneous acyline once every 2 weeks). Patients were evaluated at monthly intervals. The protocol was completed by 17/22 acyline-treated and 21/22 non-acyline-treated men. Sperm count declined to ≤1 million/ml after a mean of 7–9 weeks in both groups, and had normalized by a mean of 11–15 weeks after treatment ceased. There were no serious adverse events, and changes in body weight, serum lipids and PSA were minimal and reversible.

The authors conclude that transdermal testosterone gel plus DMPA is well tolerated and effective; they call for extended-duration studies to determine the dose of testosterone gel required to optimize spermatogenesis suppression.