Question

During a menstrual cycle, what is the purpose of the uterine lining build-up?

Answer 1

The answer to this question would be: to prepare for pregnancy.

If fertilization happens, the egg will need to attach itself to the uterus. A failure in implantation process will cause it to develop a disease or abortion. In implantation, the gamete will dig up the uterus before attaching it. After that, the embryo can connect to some blood vessel and able to take nutrient from the mother blood.