The ectocervix (also known as the vaginal portion of the cervix) has a convex, elliptical shape and projects into the cervix between the anterior and posterior vaginal fornices. On the rounded part of the ectocervix is a small, depressed external opening, connecting the cervix with the vagina. The size and shape of the ectocervix and the external opening (external os) can vary according to age, hormonal state, and whether natural or normal childbirth has taken place. In women who have not had a vaginal delivery, the external opening is small and circular, and in women who have had a vaginal delivery, it is slit-like. On average, the ectocervix is long and wide.