Menstruation is the process where the thickened and unnecessary lining of the uterus, prepared for a potential embryo, breaks down and is expelled through the vagina as blood and mucous. This cycle occurs roughly every month and lasts for about ...

The uterus develops a thick and spongy lining every month in preparation for receiving a fertilized egg. This lining is richly supplied with blood and nutrients, intended to nourish the embryo if fertilization occurs.

If the egg is not fertilized, it lives for about one day. In the absence of fertilization, the uterus undergoes changes to prepare for the possibility of a fertilized egg, thickening its lining each month.

The development of the child inside the mother’s body takes approximately nine months. The birth process is triggered by rhythmic contractions of the muscles in the uterus. These contractions lead to the expulsion of the child from the uterus, marking ...