May 31, 2019
Understanding the physiology of childbirth is one of the first steps a woman and couple can take to prepare for labor. Knowing the purpose behind what is happening to the body during labor helps immensely with mental preparation and can give a laboring woman mental AND physical fortitude during labor.
We want to begin with some basics in this childbirth education series, so that means we’re starting with an amazing part of the female body called the cervix. The cervix is a part of the uterus and is found on the lowest part connecting the uterus and vagina.
Around here, we love a good birth analogy. So here is our explanation of the role of the cervix during labor.
The baby is the treasure.
The womb is the trove.
The cervix is the door.
Contractions are the key.
Let’s start at the beginning.
There are three stages of vaginal childbirth:
– Stage 1: Labor
– Stage 2: Pushing and birth
– Stage 3: Delivery of the placenta
When labor ensues, the uterus begins contracting and moving upward, subsequently dilating (opening) the cervix from 0 centimeters to 10 centimeters.
What exactly is a contraction?
Flex and contract your bicep for a few seconds. Your bicep just became shorter and tighter. This is what happens with uterine contractions. The uterus is made up of some incredibly strong muscles that when contracting, can become strong enough to expel the baby without any pushing on the woman’s part.
This dilation happens in three phases: early labor (0-3cm), active labor (4-7cm), and transition (8-10cm).
Think of the cervix as the door to the womb, opening with a series of locks to allow for the passage of the baby through the pelvis, out the vagina, and into the mother’s arms.
The laboring process is different for every woman and each “lock” may “open” at various points during pre-labor and labor.
Lock 1: Ripening
– The softening of the cervix
– Measured in terms like firm, medium, soft
Lock 2: Dilation
– The opening of the cervix
– Measured in centimeters from 0, meaning not dilated and 10, to fully dilated
Lock 3: Effacement
– The thinning of the cervix
– Measured from 3-4 cm thick to fully effaced.
Lock 4: Position
– The moving of the cervix from a posterior position, facing the mother’s back, to an anterior position, facing the mother’s front
Variation of normal
A woman may begin labor with the cervix at 0cm dilated, 0% effaced, and completely firm. Another woman may begin labor at 4cm dilated, 75% effaced, and soft.
Generally, once all the locks are opened, a woman begins to push her baby out, or allows her body to push the baby out and enters the second stage of labor and birth.
You may find yourself wondering, “How can I help my cervix dilate or open?”, or “How can I speed up labor?”
Know this, it may take one woman several days and another three hours for the cervix to be completely open, effaced, and ripened before entering the pushing stage.
What does this mean for you?
No matter how all these changes occur, it’s important to remember that each labor is unique and there is a variation of normal. The progression described above happens (or doesn’t happen) differently for each. There is no formula to get this to happen in a specific way.
However the door is unlocked, understanding this process helps immensely with how you view labor and what is happening to your body in the moment. Whether it’s excruciating, or mildly discomforting, you understand the pain has a purpose which allows you to trust the process and help you achieve your birth goals, whatever those may be, with calming confidence.
Find ways you can help this process along here.