combination effect of pentoxifylline and l-carnitine on idiopathic oligoasthenoteratozoospermia

background: pentoxifylline (px) is a methyl xanthine derivative that influences the sperm motion characteristics and l-carnitine (l-c) is an amino acid that is naturally produced in the body. in general, separate administration of px and l-c has been reported to be effective on preserving sperm motility in vitro, and also when is consumed orally by the idiopathic oligoasthenoteratozoospermia (ioat) patients. objective: the aim of this study was to evaluate any possible effect of a combination of l-c and px on sperm characteristics and improving the type of assisted reproductive techniques (art) in a group of patients with unexplained oligoasthenoteratozoospermia. materials and methods: two hundred twelve infertile men with ioat in a double-blind, placebo-controlled, randomized clinical trial were allocated for this study. they randomized to four groups. group i received px/ and l-c (each one, twice daily), group ii, px and placebo, group iii, l-c with the placebo, and group iv, received placebo tablets. finally, we compared pre and post intervention sperm parameters and art procedures between groups. results: while the use of px and l-c are only improved sperm motility, but their combined uses improved all sperm parameters, especially the sperm count. also the combination of px and l-c was effective on improving the art procedures (p<0.01). conclusion: our results demonstrate that the combination use of px and l-c is useful in improving of sperm parameters in ioat patients and also, improve art procedures in this group of patients