Dilated Cervix

Medically reviewed by: Stephanie Curreli, MD, PhD
Last Updated: Feb 4, 2015

A fully dilated cervix is necessary for a successful vaginal birth. Once labor starts, rhythmic contractions that begin at the top of the uterus and travel down its length force the contents of the uterus toward the cervix. Since the fetus is usually positioned with its head downward, labor contractions force the head against the cervix. This action causes the cervix to stretch, which is thought to Continue Scrolling To Read More Below...

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Continued From Above... elicit a reflex that will stimulate still stronger labor contractions until a maximum effort is achieved. At the same time, the cervix dilates and, as labor continues, abdominal wall muscles are stimulated to contract and aid in forcing the fetus through the cervix and vagina to the outside.