Pregnancy: Effect of pentoxifylline on implantation and post-implantation development of mouse embryos in vitro

Previous work from our laboratory has revealed that brief exposureof mouse zygotes to 3.6 and 7.2 mM pentoxifylline reduced cellnumbers in mouse embryos reaching the blastocyst stage in vitro.Since a decrease in cell numbers may impair further development,the present study aimed to assess the implantation in vitroand the development beyond implantation of these embryos. Blastocystscultured from the one-cell stage in the presence of 5, 10 and50 µM pentoxifylline, i.e. concentrations expected inthe secretions of the genital tract after oral administration,were shown to develop normally to the egg cylinder stage invitro. Blastocysts, obtained after culture in vitro of zygotesexposed 29 h after human chorionic gonadotrophin (HCG) for 30min to 3.6 and 7.2 mM pentoxifylline, i.e. the concentrationsused for enhancing sperm function in vitro, could implant buttheir development to the egg cylinder stage was found to beimpaired. The same effect was noticed if blastocysts, grownin vitro from the one-cell stage, were exposed to 3.6 and 7.2mM pentoxifylline for 30 min in vitro 120 h after HCG. Thesefindings imply that when pentoxifylline is used to enhance spermfunction in vitro, it should be washed out of the preparationused for insemination.