Abstract: Human assisted reproductive technology（ART） is one of the most effective therapies for human infertility. In vitro culture condition and the strategy of embryo transfer are important factors of ART outcomes such as the live birth rate and the singleton pregnancies rate. Those conditions of in vitro culture include temperature, pH, oxygen concentration, medium and sequential or continuous culture. The strategy of embryo transfer involves the elective single or double embryo transfer, transfer in cleavage or blastocyst stage, and the index for selecting the best blastocyst. Based on recent studies, this review discussed above controversial problems.

Key words: Reproductive techniques, assisted, Embryo culture techniques, Embryo transfer, Blastocyst