• Presenting or your baby's presentation: This describes the part of your baby's body that is farthest down in your pelvis. Ideally, this is your baby's head.
• Effaced or effacement: This refers to how much your cervix has thinned in preparation for birth, and often is measured by percentage. If this is your first pregnancy, effacement usually begins before dilation. At 100% effaced, you are ready to deliver your baby. • Station: This refers to how far your baby's head has moved into your pelvic cavity. Each station is 1 centimeter. • Dilated or dilation: This refers to how much your cervix has opened. It is measured in centimeters. Some women begin to dilate several weeks before labor. At 10 centimeters, you are ready to start giving birth.