URL of this page: http://www.nlm.nih.gov/medlineplus/ency/presentations/100198.htm

Vaginal birth - series

Procedure, part 3

Procedure, part 3

Overview

Contractions help your cervix dilate -- or open -- so your baby can pass through the birth canal. You're fully dilated when your cervical opening measures 10 centimeters. As the cervix opens, it also thins (effaces) in preparation for delivery.

Update Date 2/6/2007

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