Learning aims
- Describing the development of the embryo from the first cells to the blastocyst
- Knowing the important stages of the preimplantation phase
- Describing the importance of these stages
- Knowing the duration of the preimplantation phase
What you should already know
- The processes during fertilization that lead to the formation of the zygote
Delving deeper
- How does the early embryo get to the uterus; how does it find its way?
- From what does the embryo nourish itself until its implantation?
- How is the blastocyst formed?
Introduction
Following a successful fertilization the preimplantation period that lasts for around 6 days ensues.
While the fertilized oocyte wanders from the ampulla through the fallopian tube into the uterine cavity, an implantation-ready blastocyst develops through cell divisions. At the end of the sixth day after fertilization the blastocyst embeds itself in the endometrium.