The womb consists of a variety of muscles and is usually referred to as the strongest muscle group in the woman's body. The two muscle groups that play the greatest role in pregnancy and childbirth are the upper muscles of the uterus body and the lower muscles of the cervix. The womb has openings, partly upwards towards the fallopian tubes and partly downwards towards the vagina. It may resemble a balloon, muscle walls that form a cavity, the muscles then end up in a canal, cervix. The cervix ends in the upper part of the wearer. If you feel far back in the vagina you can feel the uterus (the mother's mouth), the outermost part of the cervix, it feels like a round little bullet. The size of the womb can be compared to the size of a hen egg, during pregnancy it will grow and multiply its size.
Source: Wife: Text written by Pediatric Therese Sok.