What happens to the embryos in the clinic that are not implanted?

The implantation of the human embryo is the process whereby the blastocyst phase zygote is anchored to the endometrium. It is one of the phases of human embryogenesis. [Implantation begins at the end of the first week - seventh or eighth day - after fertilization of the ovule by the sperm and extends until the end of the second week - 14 days after fertilization Development of the morula prior to implantation. The division of the first cell resulting from fertilization - the zygote - gives way to the morula from the first cellular mitoses. The morula will be transformed into a set of cells called blastocyst or blastula that will adhere to the wall of the uterus during the second week after fertilization - adhesion begins on the 7th or 8th day and ends on the 14th day - the implantation will be finished.

Pro insulin undergoes extensive posttranslational modification along the production pathway .