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GnRH Analogues in the Development of a Male Contraceptive: Importance of Testosterone Substitution and Reversibility of Pituitary and Testicular Suppression

  • Gerhard F. Weinbauer
  • Eberhard Nieschlag

Abstract

GnRH agonists and antagonists are potent and selective inhibitors of gonadotropin synthesis and release resulting in suppression of spermatogenesis. For these reasons, GnRH analogues have received considerable attention as potential male contraceptives. The GnRH analogue-mediated suppression of LH is also associated with a reduction of androgen levels comparable to that seen after orchidectomy. Since androgens are indispensable for normal male physiology, their substitution is thus mandatory in clinical trials with GnRH analogues for male contraception. The evidence available so far, however, suggests that androgen therapy may decrease the antispermatogenic activity of GnRH analogues and careful attention needs to be given to androgen substitution. The present contribution deals with the antispermatogenic potency of GnRH analogues and the crucial role of androgen substitution. Emphasis is placed on preclinical studies in non-human primates and reference is given to relevant clinical trials.

Keywords

GnRH Agonist GnRH Antagonist GnRH Analogue LHRH Agonist Testicular Function 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 1990

Authors and Affiliations

  • Gerhard F. Weinbauer
    • 1
  • Eberhard Nieschlag
    • 1
  1. 1.Max Planck Clinical Research Unit for Reproductive Medicine and Institute of Reproductive Medicine of the University of MünsterGermany

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