The closer you get to the end of your pregnancy, the more you will hear about "being effaced," "effacing," or "effacement."
Effacement is the process by which the cervix prepares for delivery. After the baby has engaged in the pelvis, it gradually drops closer to the cervix; the cervix gradually softens, shortens and becomes thinner. You may hear phrases like "ripens," or "cervical thinning" which refer to effacement.
Effacement is measured in percentages. For example, your doctor or midwife may tell you that you are effaced 50%, which means you are half way to being completely effaced. When you are 100% effaced or completely effaced, your cervix is paper-thin and labor is right around the corner.
In your final weeks of pregnancy your caregivers will routinely check for effacement, and as soon as you arrive at the hospital, you will be checked for effacement. If you are a first time mom, your cervix will efface before it dilates. If you are a second time mom, your cervix will dilate before effacement.
Reprinted with permission from American Pregnancy Association