How does the sperm get into the egg?

Conception of the human body is a rather complicated process. Before you reach the egg and fertilize it, the sperm makes a long way. At the same time, only a small number of germ cells from the male seminal fluid reach the female reproductive cell. Let's take a closer look at the process of their merging and describe how the sperm enters the egg and what happens to it after penetration (fertilization).

How does the sperm move to the egg?

In unprotected intercourse, approximately 2-3 ml of seminal fluid enters the woman's vagina , which can normally contain more than 100 million active germ cells.

From the vagina, spermatozoa begin their advancement to the cervix to get into its cavity, and then the fallopian tube. The movement of male sex cells is promoted by the contractile movements of the myometrium itself. It was experimentally established that the speed of the sperm does not exceed 2-3 mm per minute.

When entering the cervical canal, male sex cells face the first obstacle on the way - cervical mucus. If it is very thick and there are a lot of it, conception may not occur, because Spermatozoa can not overcome this barrier.

Passing through the cervical canal, the sperm are in the uterine cavity, from which they go to the fallopian tube, where after ovulation an egg is located.

How does penetration of the sperm into the egg?

The fusion of male and female reproductive cells occurs in the ampullar part of the uterine tube. Approximately 30-60 minutes after intercourse spermatozoa reach the uterine cavity, and another 1.5-2 hours goes to the path to the tube. The egg is secreted by special enzymatic substances, which indicate its exact position and, as it were, "attract" spermatozoa.

A female germ cell simultaneously reaches several spermatozoa, which are attached to its shell and loosen it. At the same time only one penetrates into the egg itself. As soon as his head is inside, the flagella is discarded. Then a chemical reaction begins, as a result of which the egg shell changes, which prevents the penetration of other spermatozoa.

Talking about how much a sperm cell lives in an egg, it should be noted that most often it's 1-2 hours. Then, the shells of the spermatozoon itself dissolve and the nuclei of the 2 germ cells merge, resulting in the formation of a zygote.