effacement
Pronunciation: ih-FAYS-ment
Thinning and shortening of the cervix during labor preparation and progression.
Full Definition
The process by which the cervix gradually becomes thinner and shorter in preparation for and during labor. Effacement is measured as a percentage, with 0% representing a thick, uneffaced cervix (about 3-4 cm long) and 100% representing complete thinning where the cervix becomes part of the lower uterine segment. This process often begins before active labor in first-time mothers and occurs simultaneously with dilation in women who have previously given birth. Assessment requires digital examination and is crucial for evaluating labor progress.
Usage
Usage note: Express as percentage (75% effaced) rather than fraction. Do not confuse with cervical dilation.
In Context
- "The cervix showed 75% effacement with 4 cm dilation." — Labor examination findings
- "Effacement typically precedes dilation in nulliparous women." — Medical education text