Androgens: Testosterone and male contraception
Androgens
Testosterone and male contraception
A World Health Organization task force repor ed in 1990 on the treatment of 271 fertile men with 200 mg testosterone enanthate by weekly intramuscular injection as a contraceptive method. Two thirds became azoospermic within a mean time of 120 days. Once azoospermia had persisted for 1 year, the mean time to recovery of sperm concentration to pretreatment levels, after discontinuation of injections, was 6.7 months. Only one pregnancy occurred in 1486 months of treatment (0.8 per 100 person years). 
Decreases in FSH, LH and testicular volume were noted, but values returned to normal in the recovery phase. The contraceptive efficacy was better than for the female OCR Three men withdrew from the study because of increased aggressiveness and libido. Possible future developments include depot testosterone preparations with longer dosing intervals of several months. In order to improve the percentage of men rendered azoospermic by testosterone, other agents have been added to the regimen. These include progestogens, GnRH agonists and recently GnRH antagonists. However, none of these regimens to date has improved upon the azoospermia rate achieved with testosterone alone.
Anabolic steroid abuse
There is an increasing trend by sportsmen and women to self administer anabolic steroids (AS). They are used to develop muscle bulk, strength and enhance physique. This is of particular interest to body builders, weight lifters, sprinters and other power athletes. A recent review examined the significant health risks associated with pharmacological doses of androgens. These include altered lipid profiles increasing the risk of coronary artery disease, increased oestrogenisation leading to strokes, and cholestatic jaundice. Peliosis hepatitis, a very rare
hepatic disease consisting of blood cysts in the liver, also occurs.
Androgen-associated hepatocellular tumours have also been described. Many of these health risks are particularly associated with the orally active 17-alkylated androgens, e.g. oxandrolone, oxymetholone, methandrostenolone and stanozolol. The injectable esters testosterone enathate and nandrolone decanoate may carry less health risks but introduce the problem of needle sharing leading to sepsis, hepatitis and HIV infection. Much of the health risk information has been derived from studies of patients receiving therapeutic doses of androgens under medical supervision. The potential magnitude of risk associated with AS abuse is only just becoming apparent.
It is only recently that investigations have begun to assess the sexual function of athletes abusing AS. As early as 1938, a marked increase in erectile capacity and sex drive was noted in men being treated with testosterone propionate for impotence. In 1943, anabolic steroids were used in 101 women with a variety of endocrine disorders. Libido increased in 90%. In 20% it was noted that the stimulation was excessive. It is now apparent that the pattern of AS use in athletes differs greatly from that used in therapeutic regimens.
Pope and co-workers recently sent a questionnaire to 41 athletes drawn from 38 gymnasia on the East and West Coast of the USA. Steroids were typically taken in cycles of 4 to 12 weeks. Athletes had between 1 and 30 cycles of AS. Often several drugs are taken simultaneously (stacking) including the self administration of veterinary preparations. It was difficult to estimate the actual dose equivalency of many of the preparations to therapeutic drugs, but it was estimated that many subjects took between 10 and 100 times the doses reported in medical studies.
Anecdotal reports have suggested that athletes on low-dose androgenic anabolic steroids experience reduction in libido and even impotence. A recent controlled study looked at sexual performance objectively and compared this with the subjective impressions of sexual function in athletes who were current users of AS. This was then compared with past users and non-users of AS.
This study was revealing because it helps to resolve some of the inconsistencies of previous reports. Current users of AS reported significantly more episodes of sexual activity leading to orgasm than did past users or non-users. There was no difference between the three groups in the qualitative enjoyment of sexual activity but current and past users believed that AS enhanced sexual function.
However, 20% of current users reported difficulty maintaining erections during sexual activity. This was not reported by any past or non-users. This result helps to explain why previous studies have shown some men experiencing increased libido whereas others reported a decrease. Sexual appetite is androgen dependent but erectile function is not. Therefore, although the current AS users in this study had increased sexual thoughts, their bodies were not always able to keep pace with their desires.
Danazol
Danazol, a derivative of 17 a-ethinyltestosterone, has both progestogenic and androgenic actions. It is used mainly for the treatment of endometriosis but is also prescribed in mastalgia and menorrhagia. In endometriosis, it is administered continuously for up to 9 months. At high doses, danazol suppresses ovulation and produces infertility. At lower doses, ovulation can still occur and patients should be advised to use non-hormonal contraceptive precautions as danazol can lead to virilisation of female fetuses. 
Loss of libido is an occasionally reported side effect in some studies. In a large study of over 200 patients treated with 400 or 800 mg danazol per day, only three patients withdrew from treatment for this reason, although they all had other side effects as well. A non-randomised study compared the side effect profile of danazol and gestrinone (an antigonadotrophin with androgenic and progestogenic properties similar to danazol). Both compounds were associated with a similar incidence of reduced libido of approximately 10%.
However, a recent large European multicentre study compared danazol at a starting dose of 600 mg/day with a GnRH agonist and specifically recorded the patients’ assessments of their libido before treatment and again every 4 weeks during treatment for 6 months. In this study, a reduction in libido was recorded in 52% of 103 patients on danazol. This was a much higher incidence than in the other studies cited but probably illustrates the point that if sexual information is to be elicited from patients it must be specifically requested.
