The internal orifice of the uterus (or internal orifice of the cervix uteri or internal os) is an interior narrowing of the uterine cavity. It corresponds to a slight constriction known as the isthmus that can be observed on the surface of the uterus about midway between the apex and base.
Famous quotes containing the word internal:
“Even if fathers are more benignly helpful, and even if they spend time with us teaching us what they know, rarely do they tell us what they feel. They stand apart emotionally: strong perhaps, maybe caring in a nonverbal, implicit way; but their internal world remains mysterious, unseen, “What are they really like?” we ask ourselves. “What do they feel about us, about the world, about themselves?””
—Augustus Y. Napier (20th century)