3.3.4  Perineum and hymen

The skin-covered muscular area between the vaginal opening and the anus is called the perineum. It has strong muscles and its own nerve supply, and it helps to support the contents of the pelvic cavity. The hymen is a fold of thin vaginal tissue which partially covers the vaginal entrance in girls. It can be torn during strenuous exercise, as well as by the first sexual penetration.

3.4  Internal female reproductive organs