What is Blastocyst Embryo Transfer ?
The first IVF human pregnancy was achieved by blastocyst transfer. Blastocyst transfer is claimed to be more physiological than pro-nucleate or cleaved-embryo transfer is as it mimics nature more closely. As the embryo advances in the development, after 5-6 days it becomes a blastocyst. This has an outer thin layer of cells which will later form the placenta, and an inner cell mass which will develop into the fetus. A blastocyst has about 120 cells. A blastocyst gives a better idea of the competence of an embryo and has a higher chance of implantation than a cleaved embryo. In conventional culture medium, about 20% of embryos will develop into blastocysts. Recently, the use of sequential culture medium (the embryos are cultured in different media according to their stage of growth) has enabled a larger number of embryos to develop into blastocysts. However, up to 40% of patients will not grow blastocysts and will not have blastocyst embryo transfer. The rational behind a blastocyst tra
