Gynaecomastia and anabolic steroids

• suppression of spermatogenesis and gynecomastia are frequent consequences of androgen use
  • high doses of anabolic androgenic steroids (AAS) suppress the hypothalamic-pituitary-gonadal axis due to negative feedback, and it may take weeks or months (sometimes longer) for the axis to recover
    
    
    • atrophy of the seminiferous tubules during this time may result in subfertility/infertility
      
      
    • even after discontinuation of AAS, subjects may continue to encounter symptoms of hypogonadism (low libido, erectile dysfunction, and low vitality) until the axis recovers
      • although no randomized trials exist, anecdotal reports suggest that use of clomiphene citrate may hasten the recovery of the gonadal axis
        
        
    • gynecomastia is also seen in athletes using AAS, specifically aromatizable androgens e.g. testosterone
      • a proportion of testosterone is converted by aromatization to oestradiol (an endogenous oestrogen) in males - however with supraphysiological amounts of testosterone then the levels of oestradiol are also increased to supraphysiological levels
      • many athletes resort to off-label use of tamoxifen (oestrogen receptor antagonist) and aromatase inhibitors to circumvent this side effect
        
        
    • women using AAS experience the usual adverse effects of hyperandrogenism such as breast atrophy, irregular menses, hirsutism, male-pattern baldness, hoarse voice, and clitoromegaly

Reference:

• 1) Basaria S.Androgen abuse in athletes: detection and consequences. J Clin Endocrinol Metab. 2010 Apr;95(4):1533-43.