In fact, a women is not technically considered pregnant until the blastocyst (sometimes health care providers call this the "products of conception") implants in the uterus.
Usually it takes five days for the blastocyst to travel through the fallopian tubes and into the uterus where it implants in the lining of the uterus around the sixth day.
If the blastocyst does not implant, it will be absorbed into the body without the mother having any indication that a sperm and egg met.
Implantation, the process in which the blastocyst implants into the uterine wall, occurs approximately six days after conception.
Before the sperm and egg (known at this point as the blastocyst) implant in the uterus, a pregnancy is not guaranteed.
At this stage the blastocyst consists of 200 to 300 cells and is ready for implantation.
The blastocyst first adheres to the wall then moves into the uterine tissue.
The cells in the blastocyst continue to divide and grow to form an embryo.
The zona pellucida disappears and the morula becomes a blastocyst.
This composition is a blastocyst that contains an outer shell.