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Cervical effacement and dilation

Effacement (thinning)

Head of fetus down near cervix before birth, with detail of cervix not effaced and detail of effaced or thinned cervix as delivery nears.
slide 1 of 2
slide 1 of 2, Effacement (thinning),

As labor nears, the fetus's head drops down into the pelvis and pushes against the cervix. The cervix begins to thin (efface), sometimes over a few weeks.

Dilation (opening)

Head of fetus down near cervix before birth, with detail of cervix closed and detail of cervix open (dilated) as delivery nears.
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slide 2 of 2, Dilation (opening),

At the same time, the cervix also begins to open (dilate).

Current as of: July 10, 2023

Author: Healthwise Staff
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