What does the process of implantation involve?

The process of implantation specifically involves the embedding of a fertilized egg, also known as a blastocyst, into the uterine lining. Following fertilization, the zygote travels down the fallopian tube and undergoes several divisions, ultimately forming a blastocyst by the time it reaches the uterus. Once in the uterus, for successful pregnancy to occur, this blastocyst must attach to the endometrial lining. This attachment allows for the establishment of a connection between the mother and the developing embryo, facilitating nutrient and oxygen exchange necessary for development. Without successful implantation, the pregnancy cannot advance, making this process critical in early development. Other processes listed, such as the release of an ovum, the division of a zygote, or the delivery during childbirth, are important events in reproduction but are not part of the implantation process itself.