The effect of all-trans retinol on in vitro mouse embryo''s developmental competence

Background: all-trans retinol is a biological antioxidant scavenging the ros in the cell culture. objectives: this study was conducted to investigate the effect of all-trans retinol in fertilization and culture medium on mouse embryo's develop-mental competence. methods: this study was designed into two experiments. in the first experiment, in vitro mature oocytes were co-cultured with sperm in fertilization medium containing different concentrations of all-trans retinol (0, 1, 5, and 10 µm). after fertilization, zygotes in each group were separately cultured in czb culture medium for 5 days to the blastocyst stage. in the second experiment, in vitro produced zygotes were cultured in czb culture medium containing different concentrations of all-trans retinol (0, 1, 5, and 10 µm) for 5 days to the blastocyst stage. results: in the first experiment, the blastocyst formation rate significantly increased by 5 µm in all-trans retinol, which was more than those of the other groups. also, percentage of grade one embryos was significantly higher in the presence of 5 µm all-trans retinol than those in the presence of 0 and 1 µm all-trans retinol. in the second experiment, different concentrations of all-trans retinol could not alter blastocyst formation rate; however, the percentage of grade one embryo was higher in the presence of 10 µm all-trans retinol than that of the control group. conclusions: these results showed that supplementation of fertilization medium with 5 µm all-trans retinol could improve mouse embryo's development and morphology. on the other hand, supplementation of embryo culture medium can improve mouse embryo morphology without any effect on embryo developmental competence.