Pentoxifylline: actions and applications in assisted reproduction.

Data are presented covering various studies on the use of the phosphodiesterase inhibitor pentoxifylline (PF) in the sperm preparation for procedures in assisted reproduction. Significant improvements have been shown in the fertilization rate of oocytes along with a reduced risk of failed fertilization cycles utilizing oligo/asthenozoospermic semen samples. Fertilization is also improved for normozoospermic samples when the acrosome reaction is suboptimal. PF has proven effects on sperm motility, increasing the proportion of hyperactivated spermatozoa. It can also enhance the acrosome reaction and this may be the more relevant function for clinical prediction. There is a further action as a suppressor or scavenger of reactive oxygen species although higher concentrations than that in current clinical use may be required to optimize this effect. PF should be washed out of the sample used for insemination to avoid inhibiting the completion of oocyte maturation.