title: Preliminary study of letrozole use for improving spermatogenesis in non-obstructive azoospermia patients with normal serum FSH.
abstract: We investigated whether letrozole (2.5 mg day(-1)) improves sperm count in non-obstructive azoospermia (NOA) patients. Four men were included in this study, and they had folliculo-stimulating hormone and other hormone levels within the normal range and no varicoceles or chromosomal aberrations. These four patients were administered letrozole for 3 months. Sperm count, testicular volume, gonadotropin, testosterone (T) and estradiol (E2) blood levels were assessed before, during and 1 week after the suspension of treatment. All patients showed spermatozoa in their ejaculate, increased gonadotropin and T levels and lower E2 levels (P<0.05 in all cases), when letrozole was administered. This suggests that letrozole treatment might improve sperm count in an NOA sub-population; however, more studies, including the proper controls, are needed to confirm its efficacy.
authors.affiliation: Andros-Italia, Outpatient Clinic of Ferrara, Ferrara 44121, Italy. giorgiocavallini@libero.it
authors.forename: Giorgio
authors.initials: G
authors.lastname: Cavallini
authors.forename: Giovanni
authors.initials: G
authors.lastname: Beretta
authors.forename: Giulio
authors.initials: G
authors.lastname: Biagiotti
mesh_terms: D047072:Aromatase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D053713:Azoospermia / Q000188:drug therapy* / Q000503:physiopathology; D004958:Estradiol / Q000097:blood; D005640:Follicle Stimulating Hormone / Q000097:blood*; D006801:Humans; D000077289:Letrozole; D008297:Male; D009570:Nitriles / Q000494:pharmacology / Q000627:therapeutic use*; D013076:Sperm Count; D013091:Spermatogenesis / Q000187:drug effects*; D013739:Testosterone / Q000097:blood; D014230:Triazoles / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D047072:Aromatase Inhibitors; D009570:Nitriles; D014230:Triazoles; D013739:Testosterone; D004958:Estradiol; D000077289:Letrozole; D005640:Follicle Stimulating Hormone