What is Blastocyst Transfer and How Does That Differ From 2-3 Day Embryo Transfer Techniques?
Taken from the Advanced Fertility Center of Chicago: http://www.advancedfertility.com/blastocy.htm. A blastocyst is an embryo that has developed for five days after fertilization. At this point the embryo has two different cell types and a central cavity. The surface cells, called the trophectoderm, will become the placenta, and the inner cells, called the inner cell mass, will become the fetus. A healthy blastocyst should hatch from its outer shell, called the zona pellucida by the end of the sixth day. Within about 24 hours after hatching, it should begin to implant into the lining of the mother’s uterus. The ultimate goal of in vitro fertilization (IVF) and embryo culture is to provide high quality embryos which are capable of continued normal development and result in live births. However, under standard IVF culture conditions, only about 20-40% of human embryos will progress to the blastocyst stage after 5 days of culture. This low rate of embryo development is the result of a les
