Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
In the context of pregnancy, labor, and birth, dilation refers to the widening and opening of the cervix to prepare for childbirth. It is measured in centimeters from 0 (closed) to about 10 (fully dilated), indicating readiness for delivery.
Related terms
Effacement: The thinning and shortening of the cervix during late pregnancy and early labor.
Contractions: The tightening and relaxing of uterine muscles intended to help dilate and efface the cervix during labor.