Fertilization and early embrology: Vero cell effect on in-vitro human blastocyst development: preliminary results

Asynchrony between embryo and uterine environment is one ofthe major limits in human in-vitro fertilization (TVF). A culturesystem which could prolong culture time and increase embryoniccleavage rate and viability would improve success rates. UsingVero cells, an in-vitro co-culture system was developed to investigateand promote human embryo development. Vero cells provide goodsupport for human early embryos up to the blastocyst stage.When fertilized embryos were co-cultured, 68% of them reachedthe blastocyst stage. Pregnancy rate was 50% per transfer inpatients with several previous failures of implantation. A significantincrease in clinical pregnancy rate was also demonstrated whenzygotes were maintained on Vero cell monolayer for only 24 h.The beneficial effect of the feeder layer may be through therelease of embryotrophic factors and the detoxification of theculture medium by the cells. Co-culture is a new concept inassisted reproduction.