There are several chemicals in women which have a role in the mechanism of pregnancy. These chemicals such as the luteinizing hormone also known as LH and human chorionic gonadotropin also known as known as HCG are called hormones. Other hormones which are important in pregnancy include estrogen and progesterone. All of these hormones are under control of a system in the human body known as the endocrine system. The diagram you see shows you how the cycle would occur over a period of 5 weeks. A typical female menstrual cycle lasts 28 days.
At the beginning of the cycle meaning when the day when there is blood or menstrual flow, the walls of the female uterus have to be prepared before the ovary can release an egg. This egg is essential in the process of pregnancy since it is only when your sperm and your wife’s egg interact that pregnancy can begin, this interaction is called fertilization. In order to prepare for fertilization the levels of estrogen in the body increase and the walls of the uterus become thicker which slows and eventually stops the menses. It keeps on acting on the walls and eventually makes it release mucus by mid cycle in order to prepare for the egg.