An anatomical structure of the female genitalia often described as a collar or semicollar of tissue surrounding the vaginal orifice. A wide range of anatomic variation is seen in the prepubertal child, pubertal child, adult, and older adult. In the evaluation of children (prepubertal and pubertal), the hymen is often described in terms of shape, color, developmental estrogen effect, presence of anatomical variations, and other visible findings.