Influence of Testosterone Substitution on Sperm Suppression by LHRH Agonists

Abstract

To investigate the effect of LHRH (GnRH) agonists on sperm suppression, we studied the effect of a depot preparation of D-Trp⁶ LHRH in 10 normal men for 30 weeks. In addition, to determine the role of androgenic substitution on sperm suppression, the volunteers were divided into two groups: group 1 (n = 5) received a low dose T substitution (125 mg of T enanthate every month), while group 2 (n = 5) received a normal T substitution (120 mg of T undecanoate every day). Four men became azoospermic in group 1 and none in group 2. Moreover, administration of additional T injections in 1 volunteer of group 1 resulted in the reappearance of spermatozoa in the ejaculate. Return to the low dose therapy produced azoospermia. These results suggest that testosterone supplementation supports spermatogenesis.

Prostate-Sparing Effects in Primates of the Potent Androgen 7α-Methyl-19-Nortestosterone: A Potential Alternative to Testosterone for Androgen Replacement and Male Contraception1

“…It has been widely suspected that exogenous androgens used in hormonal male contraceptive regimens may raise intratesticular androgen concentrations sufficiently to stimulate spermatogenesis, attenuating the antifertility impact of the contraceptive (50,(53)(54)(55). The following lines of evidence suggest that 5␣-reduced metabolites of testosterone actually mediate this undesirable effect.…”

Male Contraception

“…261 By contrast, extreme androgen doses used experimentally in healthy men can produce idiosyncratic hypomanic reactions in a minority. 200,264,265 Synergistic combinations reduce the effective dose of each steroid, and minimizing testosterone dosage could enhance spermatogenic suppression if high blood testosterone levels counteract the necessary maximal depletion of intratesticular testosterone 266,267 as well as reduce androgenic side effects. 263 Androgen Combination Regimens Combination steroid regimens using nonandrogenic steroids (estrogens, progestins) to suppress gonadotropins in conjunction with testosterone for androgen replacement have shown the most promising efficacy, with enhanced rate and extent of spermatogenic suppression compared with androgen-alone regimens.…”

“…When combined with testosterone, GnRH agonists suppress spermatogenesis but rarely achieve azoospermia, 266,267,295 being less effective than androgen/progestin regimens. Blockade of GnRH action by GnRH receptor blockade with synthetic analogues or GnRH immunoneutralization would eliminate LH and testosterone secretion requiring testosterone replacement.…”

Hormonal, chemical and thermal inhibition of spermatogenesis: contribution of French teams to international data with the aim of developing male contraception in France

“…The third team, Bouchard and Garcia [27], tested the efficacy of long-acting LHRH agonist in ten volunteers; five men received in addition one low monthly dose of TE (125 mg by intramuscular (IM) injection) and the remaining five received a more physiological dose of testosterone (120 mg/day oral TU). The treatment was ineffective as soon as androgen replacement was sufficient: in the first group, 4 of 5 men became azoospermic but spermatogenesis returned as soon as injected testosterone was increased.…”