Objective:To investigate whether the early developmental dynamic phenotypes and kinetic parameters of embryos used for embryo selection are affected by the differences in the components of culture media utilized.Methods:The clinical data of patients undergoing in vitro fertilization (IVF) at Center for Reproductive Medicine and Genetics of People's Hospital of Guangxi Zhuang Autonomous Region from October 2016 to December 2018 were analyzed in a retrospective cohort study. According to the different culture media utilized, IVF cycles were divided into Cook group and Vitrolife group. After 1∶1 propensity-score matching (PSM), 59 IVF cycles were included in each group. Time-lapse imaging technology was used to analyze the early developmental dynamics of normal fertilized embryos between insemination and 68 h post insemination. Seven developmental dynamic phenotypes of embryos were annotated and the differences in the composition of dynamic phenotypes were compared between the two groups. Thirteen early developmental kinetic parameters were calculated, and the differences in the kinetic parameters of normal dynamic phenotypic embryos between the two groups were compared. According to the two published time-lapse embryo selection algorithms, the hierarchical distribution of normal dynamic phenotypic embryos of two groups was compared. Results:1) In Cook group, the composition of developmental dynamic phenotypes of embryos were 54.0% normal phenotype, 3.0% abnormal first cytokinesis (A1 cyt), 17.4% abnormal cleavage (AC), 5.2% reverse cleavage (RC), 3.2% chaotic cleavage (CC), 3.5% multinucleation (Mn) and 13.7% mixed phenotype, which were 49.3%, 4.0%, 19.1%, 7.5%, 2.1%, 6.4% and 11.6% in Vitrolife group, respectively. No statistically significant differences were observed between the two groups for the composition of dynamic developmental phenotypes ( P>0.05). 2) Compared with Vitrolife group, the 13 developmental kinetic parameters (tPNa, tPNf, t2, t3, t4, t5, t6, t7, t8, cc2, s2, t5_PNf and t8_PNf) of normal dynamic phenotype embryos in Cook group were slightly longer, and the average number of blastomeres in 68 h post insemination (EB68hpi) was less, but the differences were not statistically significant (all P>0.05). 3) No significant difference in hierarchical distribution of embryos was observed between Vitrolife group and Cook group according to algorithm A ( P>0.05). The difference of embryo hierarchical distribution between the two groups was statistically significant according to algorithm B ( P=0.040), the proportion of grade A + embryos in Vitrolife group was higher than that in Cook group [59.8% (125/209) vs. 43.3% (94/217)], and grade C proportion was lower [9.6% (20/209) vs. 20.3% (44/217)]. Conclusion:Although the early developmental dynamic phenotypes and kinetic parameters of embryos were not affected by the differences between Cook and Vitrolife sequential culture media, the applicability of different time-lapse embryo selection algorithms to the culture media is different, the embryo culture media utilized should be considered when selecting or constructing the algorithms.

Objective:To investigate whether the early developmental dynamic phenotypes and kinetic parameters of embryos used for embryo selection are affected by the differences in the components of culture media utilized.Methods:The clinical data of patients undergoing in vitro fertilization (IVF) at Center for Reproductive Medicine and Genetics of People's Hospital of Guangxi Zhuang Autonomous Region from October 2016 to December 2018 were analyzed in a retrospective cohort study. According to the different culture media utilized, IVF cycles were divided into Cook group and Vitrolife group. After 1∶1 propensity-score matching (PSM), 59 IVF cycles were included in each group. Time-lapse imaging technology was used to analyze the early developmental dynamics of normal fertilized embryos between insemination and 68 h post insemination. Seven developmental dynamic phenotypes of embryos were annotated and the differences in the composition of dynamic phenotypes were compared between the two groups. Thirteen early developmental kinetic parameters were calculated, and the differences in the kinetic parameters of normal dynamic phenotypic embryos between the two groups were compared. According to the two published time-lapse embryo selection algorithms, the hierarchical distribution of normal dynamic phenotypic embryos of two groups was compared. Results:1) In Cook group, the composition of developmental dynamic phenotypes of embryos were 54.0% normal phenotype, 3.0% abnormal first cytokinesis (A1 cyt), 17.4% abnormal cleavage (AC), 5.2% reverse cleavage (RC), 3.2% chaotic cleavage (CC), 3.5% multinucleation (Mn) and 13.7% mixed phenotype, which were 49.3%, 4.0%, 19.1%, 7.5%, 2.1%, 6.4% and 11.6% in Vitrolife group, respectively. No statistically significant differences were observed between the two groups for the composition of dynamic developmental phenotypes ( P>0.05). 2) Compared with Vitrolife group, the 13 developmental kinetic parameters (tPNa, tPNf, t2, t3, t4, t5, t6, t7, t8, cc2, s2, t5_PNf and t8_PNf) of normal dynamic phenotype embryos in Cook group were slightly longer, and the average number of blastomeres in 68 h post insemination (EB68hpi) was less, but the differences were not statistically significant (all P>0.05). 3) No significant difference in hierarchical distribution of embryos was observed between Vitrolife group and Cook group according to algorithm A ( P>0.05). The difference of embryo hierarchical distribution between the two groups was statistically significant according to algorithm B ( P=0.040), the proportion of grade A + embryos in Vitrolife group was higher than that in Cook group [59.8% (125/209) vs. 43.3% (94/217)], and grade C proportion was lower [9.6% (20/209) vs. 20.3% (44/217)]. Conclusion:Although the early developmental dynamic phenotypes and kinetic parameters of embryos were not affected by the differences between Cook and Vitrolife sequential culture media, the applicability of different time-lapse embryo selection algorithms to the culture media is different, the embryo culture media utilized should be considered when selecting or constructing the algorithms.