Detect cervical changes

As your due date approaches, your health care provider might do a pelvic exam to detect cervical changes. As your body prepares for birth, your cervix will begin to soften, open (dilate) and thin (efface). Progress is typically expressed in centimeters (cm) and percentages. For example, your cervix might be 3 centimeters dilated and 30 percent effaced. When you're ready to push your baby out, your cervix will be 10 centimeters dilated and 100 percent effaced.