RESUMO
To determine the efficacy of L-carnitine on the fertility and semen parameters in cases of idiopathic oligoasthenozoospermia. Placebo-controlled, single-blind clinical study. One hundred twenty one men with sperm density <10,000,000 sperm/mL, and total sperm motility < 50%, normal serum gonadotrophins and testosterone, and a fertile partner were enrolled. Patients were prescribed L-carnitine or placebo for 6 months. Semen and blood samples were collected before and after therapy. The pregnancy rate [PR] in the treatment group was 28.3% compared with 5.1% in the placebo group. There was a statistically significant difference in the PR between the two groups. The treatment group had statistically higher levels of sperm density and total sperm motility. There were no differences between the 2 groups in seminal fluid volume and sperm morphology. It may be concluded that L-carnitine is clinically helpful for the treatment of idiopathic oligoathenozoosperima