In case you didn't know, the cervix is super cool...almost a cool as the placenta! But maybe that's the birth nerd in me coming out. Before we get into the nitty gritty of understanding the assessment of your cervix during labour, let's revisit grade 8 sex ed!
Fun fact: if you look at the cervix from below, it bears a striking resemblance to the head of a penis. Seriously, Google it!
What is a Cervix?
The cervix is simply the lower part of the uterus and, in labour, it opens like a beautiful blooming flower. There you have it, our in-depth anatomy lesson is over, and as a bonus you get your birthing visualization for the day:
Your Pre-Labour Cervix Cannot Predict the Future
Just an important side note before we move on to the purpose of this article (man, I'm getting side-tracked today): your cervix is not a flipping fortune teller! As amazing as it is, it cannot predict when you will go into labour. Just ask around, and I’m sure you’ll find plenty of women whose cervix was 0 centimeters dilated and 0% effaced less than 24 hours before they went into labour. And there are other women whose cervix was 3 or 4 centimeters dilated for weeks before they went into labour. So why do so many care providers check for dilation before the onset of labour, other than the uncommon medical reasons that may make it necessary? Good question! Let me know if you can give me an answer.
Your Cervix in Labour
Okay, now that I have already thrown all of these fancy terms at you, like "effaced" and "dilated", in my above rant, let's get started.
There are 6 ways to progress in labour, but your birth attendants will likely judge your progress by three measurements: effacement, dilation and descent. It helps to understand the labour language your birth attendants use and how it translates into what’s happening in your body.
6 Ways to Progress
Remember that dilation isn’t the only way to progress in labour. Don’t be discouraged if your healthcare provider announces “You’re still four centimetres”. Ask about the other progress you may have made, such as effacement.
Effacement means your cervix is thinning. During an internal exam, your birth attendant will measure how far effaced you are in terms of a percentage. 0 percent effaced means your cervix has not started thinning, 50 percent effaced means it is halfway there, and 100 percent effaced means your cervix is totally thinned.
Dilation refers to how far open your cervix is. During an internal exam, your health care provider will use his or her fingers to estimate your dilation in centimetres. Your HCP will give you a number that ranges between 0 and 10. The first 4cm (early labour) usually takes the longest. And trust me, it can take a very long time! Once you get to 10cm (meaning no cervix left), it is go time to start pushing!
One thing to keep in mind about dilation is that it is a matter of opinion. They are not going in your vagina with a ruler, your HCP just uses his/her fingers! That means that it is all subjective depending on the person who assesses you. If you haven't progressed in 2 hours, but have had two different people assessing you, consider the fact that you probably have progressed, but that Nurse Jane and Doctor Doe simply have different ideas of what "6cm" feels like.
Don’t be discouraged if you are not progressing at the “average” rate of 1 centimetre of dilation an hour. This is simply an obstetrical rule of thumb, and not a rule necessarily followed by your cervix. Don’t let anyone put a time limit on your labour.
Descent means how far the baby’s head is in the pelvis. During an internal exam, your healthcare provider will determine to what station the baby has descended. Station zero is the middle of the pelvis and each centimetre above or below marks another station. If your baby is -4 then he is four centimetres above zero station. If he is +4 then your baby’s head has descended all the way through the pelvis. Yay!
Yes, you are about to hear the "everyone is different" speech! Your cervix may change before labour begins, and it may not. You might have days of early labour to bring about the initial changes in your cervix, or you might not even notice it happening. You might dilate at 1cm and hour, and you may not. If you are not dilating to the satisfaction of the people watching you, you have a few options:
A) ask that the same person assesses you each time, so that changes can be more easily perceived.
B) ask what other progress you have made, such as effacement or decent.
C) tell everyone to f*&# off
Kiss-ass doula, pretty okay-ish mom, spreadsheet enthusiast, punctuality freak, ice cream addict.