Your Cervix is Not a Crystal Ball

It is around the 38th week of pregnancy.  During the prenatal appointment, the OB does a cervical exam and annouces: “You are 2 cm dilated, your baby will be here soon!”.  The week passes and the next week and perhaps even the next week…but still no baby.

OR

It is around the 40th week of pregnancy and at each appointment from 36 weeks on a vaginal exam has been performed. Each time the OB declares,”You are not dilated at all.”

Let me let you in on a secret, your cervix is not a crystal ball. It cannot predict when labor will start.  Nor can it predict if you will deliver before, after or even on your due date.  The cervix can do many wonderful things, but let’s not give the cervix more credit than it is due - a cervix cannot predict the future.

A cervical exam may satisfy some curiosity and of course any sign of dilation can be exciting.  Furthermore, each bit of dilation that occurs * before * abor is less that must happen * during * labor.  However even if cervical change is felt, and especially if the care provider adds the comment that labor will probably be soon, this information can make the last weeks of pregnancy the longest of the entire pregnancy. Now, every day seems to be on high alert for impending labor and then each day that it doesn’t happen may be a disappointment.  The discomforts of late pregnancy may be felt more acutely. Family members might even travel to be in town for the big day creating the whole “watched pot” effect.  Instead of holding a baby - everyone is just looking at that belly as it waiting for it to pop.  It is in this context that an elective induction may be encouraged and agreed to because everyone is mentally exhausted from being told the baby would be here any second.

On the other hand, if an exam is done and nothing is happening - it is easy to lose confidence that the body can do its job or feel that the pregnancy will last forever  It is completely normal for dilation not to occur until actual labor, but often exams make people feel that their bodies are not working correctly. When an discouraged person has a provider who starts talking about induction (or in some cases surgery) dates, she may agree because obviously she will not go into labor on her own any time soon and in the back of her mind she thinks her body may not even be capable of spontaneous labor.

The cervix is a a unique creature.  Some will naturally dilate prior to labor, some will not.  Some will dilate and efface slowly over time; but many will only do so with the advent of contractions.  The bottom line is that a cervical exam only tells the story of what is going on at the time of that exam.  It tells nothing about what will happen…even later that day.  A cervix does not need to reach a certain point for contractions to start, just the opposite.  Contractions will open a cervix when the time is right no matter what that cervix has been up to prior to that moment.

No evidenced based reason exists for routinely doing cervical exams during the final weeks of pregnancy. It is more a matter of “this is what we have done for a long” time rather than research. Having a cervical exam is entirely up to each person. There are circumstances where a vaginal exam can be helpful, but done routinely for the vast majority of people, a cervix check provides no predictive clinical information and it is both uncomfortable and invasive. They actually also carry some amount of risk (I once had a doula client who had an exam that broke her bag of water and thus meant she had to be induced producing a late term preemie).

If you are curious and want to know what is happening in there, go for it, but don’t give your cervix more credit than it deserves!

(Note from Maria – This blog was originally published in 20006 on my “mommy” blog Life in the Slow Lane , then moved to my first doula blog Belly Up Baby around 2009 and now lives here and is my most commonly read or quoted post. Over time, it has been adapted a bit but the basics remain the same. Both the blog and the phrase “your cerix is not a crystal ball” are coppyrighted so please share only with proper credit. Thank you! )