Spermatogenic Rebound Phenomenon After Administration of Testoster One Propionate*

Effect of Long-Term Testosterone Oenanthate Administration on Male Reproductive Function: Clinical Evaluation, Serum Fsh, Lh, Testosterone, and Seminal Fluid Analyses in Normal Men

“…This is in marked contrast to the findings of Reddy & Rao (1972) and Heller et al (1970), who reported an induction of azoospermia in normal males after daily injections of 25 mg propionate for 60 days and weekly injections of 200 mg TOe for four months, respectively. However, other reports on the rebound phenomenon also indicate that sperm counts do not fall to azoospermic levels in all patients treated (Heller et al 1950;Heckel et al 1951;Heckel 8c McDonald 1952;Charny 1959), and some investigators even found a complete absence or only marginal inhibi¬ tion of spermatogenesis by high doses of TOe (Heinkc 8c Tornati 1956) or various other esters (Joël 1960) in some of their cases. This most likely suggests a substantial individual variation of thresholds for a induced suppression of spermatogenesis.…”

Endocrine correlates of reproductive development in the male tree-shrew (Tupaia belangeri) and the effects of infantile exposure to exogenous androgens

“…The spermatogenic capacity of animals that had recovered from infantile testosterone exposure was significantly higher than the corresponding control groups at the end of normal development as indexed by the greater weight of the testes and epididymides in the former group. This observation has the characteristics of the classically described ''rebound phenomenon'' in which testosterone depression of pituitary and testis function in oligospermic men was followed by a recovery of spermatogenesis to above pre-treatment status following discontinuation of testosterone administration (Heller et al, 1950;Heckel et al, 1951). The improved spermatogenic condition of tree-shrews recovering from androgen inhibition is possibly attributable to an action of testosterone in increasing the mitotic activity or decreasing the attrition of gonocytes which normally occurs during the infantile period or a stimulation of Sertoli cell proliferation resulting in increased spermatogenic capacity of the seminiferous tubules.…”

Biennial Review of Infertility

“…Third, there has been a so-called testosterone rebound therapy used since the 1950s for the treatment of idiopathic male infertility [ 121 ] in which after testosterone injection therapy resulting in azoospermia, its discontinuation led to increase in semen parameters above baseline with resulting pregnancies. This therapy had misled some clinicians thinking that testosterone is a legitimate treatment option for low sperm concentration.…”

“…Signi fi cant differences in clinical pregnancy and live birth rate were found with transdermal testosterone pre-treatment compared to controls [ 114,115 ] . Neither adjuvant therapy by DHEA, rLH or recombinant administration nor the use of aromatase inhibitors resulted in altered clinical pregnancy rates [ 112,113,116,121 ] . In line with this, a Cochrane review [ 122 ] on LH supplementation shows no evidence for statistical differences in pregnancy rates.…”