Some men with severely defective sperm production commonly have excess aromatase activity, reflected by low serum testosterone and relatively elevated estradiol levels.
Aromatase inhibitors can increase endogenous testosterone production and serum testosterone levels. Treatment of infertile males with the aromatase inhibitors testolactone, anastrazole, and letrozole has been associated with increased sperm production and return of sperm to the ejaculate in men with non-obstructive azoospermia. Use of the aromatase inhibitors anastrazole (1 mg/day) and letrozole (2.5 mg/day) represent off-label use of these agents for impaired spermatogenesis in men with excess aromatase activity (abnormal testosterone/estradiol [T/E] ratios). Side effects have rarely been reported. Randomized controlled trials are needed to define the magnitude of benefit of aromatase inhibitor treatment for infertile men.
Written by:
Schlegel PN. Are you the author?
Department of Urology, Weill Cornell Medical College, New York, New York, USA.
Reference: Fertil Steril. 2012 Dec;98(6):1359-62.
doi: 10.1016/j.fertnstert.2012.10.023
PubMed Abstract
PMID: 23103016
UroToday.com Male Infertility & Reproduction Section