The lower portion of the uterus. The cervix is the part of the uterus that keeps the fetus from falling out of the uterus. During labor, the cervix thins and dilates to permit passage of the infant out of the uterus and into the vagina.
The lower portion of the uterus. The cervix is the part of the uterus that keeps the fetus from falling out of the uterus. During labor, the cervix thins and dilates to permit passage of the infant out of the uterus and into the vagina.