Blastocysts

A blastocyst is an early stage of embryonic development of mammals, including humans. It consists of a sphere of cells with a fluid-filled cavity at its center. It forms five to seven days after an egg is fertilized and consists of two cell types: the inner cell mass and the outer trophoblast. The blastocyst is a key stage in the embryo's development, as the inner cell mass gives rise to the fetus while the trophoblast will form the placenta. Blastocysts also have a variety of uses in assisted reproductive technologies, such as in vitro fertilization (IVF) and preimplantation genetic screening (PGS). These technologies provide an effective way for couples with fertility issues to conceive and for individuals to identify potential genetic disorders in their embryos before implantation.