What's the Deal with Vaginal Exams During Pregnancy?
Updated: Oct 28
By 40 weeks of pregnancy I’ll have to admit that I, like many women, was curious about my cervix. Was it doing anything in there? I hadn’t had any signs of cervical chang
e (mucous, “bloody show”), but maybe it was a little dilated. Maybe it was starting to efface. Hopefully it was at least soft!
Most women cared for by obstetricians in the U.S. have got some kind of an idea about the answer to those questions by the time they are “at term”, because vaginal exams in late pregnancy are extremely common. Most women accept them as a matter of course. Their doctors do them routinely, so they must be beneficial, right? They certainly couldn’t be harmful, anyway. And who doesn’t want to know whether they’ll be going into labor soon?
If only it were that simple.
To make an educated decision about any intervention, it’s important to understand what the procedure, drug, test, etc. involves as well as its inherent benefits and risks. Let’s start with a description of what a vaginal exam involves. During pregnancy, these are examinations of the cervix, often performed weekly from 36 weeks of pregnancy up to the time of birth. During an examination, the care provider, with a sterile glove on his/her hand, places the index and middle finger into the vagina and assesses the situation. He/she will be feeling for cervical ripeness or softness, effacement (the “thinning” of the cervix), and dilation (how far open the cervix is). The position of the cervix – posterior (toward mother’s back) or anterior (toward mother’s front), station of descent – how far down into the pelvis the baby has come, and presentation – head-down or breech and which way baby is facing, may also be noted.
That seems like a lot of information! Good things to know, right? Well, what are the benefits of learning all of these things about your cervix? Does it tell you how soon labor is likely to begin? No. A mother with “nothing going on” can go into labor within a day or two, and a mother who is effaced and dilated a few centimeters can walk around that way for weeks. Does it tell you how long labor is likely to last? Not really. So why are these exams performed? What benefit do they confer in exchange for their inherent indignity and discomfort?
With the exception of the presentation of the baby, which, if it turns out to be something other than head-down, will likely affect your choices surrounding the birth and which, by the way, can usually be ascertained by external palpation of the uterus*, the information gained in a pre-labor vaginal exam isn’t particularly beneficial to you, the mother. It satisfies curiosity, sure, and it lets the care provider know a couple of things – whether your cervix is favorable for induction (I will be posting in the future about the bishop’s score and what that has to do with all of this), and, when you present in labor, whether your cervix has changed since your last exam. The second part is a little helpful but certainly not necessary, and as for the first part, well, the usefulness of that information depends on whether you are planning to consent to an induction.
OK, so there is a little bit of information to be gained from a vaginal exam. Its value is questionable, especially when the exams are done as a routine procedure rather than for a particular indication, but it’s a pretty minor, low-tech procedure, right? Yes, it’s low-tech, but it’s not without risk. First of all is the psychological effect of the exam. It’s painful (moreso than exams you received when not pregnant), which is in and of itself a consideration. Also, finding out that you are three centimeters dilated can seem pretty exciting. You’re going into labor any moment, right? Not necessarily. Or, you find out that your cervix is high, closed, posterior, and thick. Bummer! It’s going to be a while, right? Maybe not. Remember, the findings of the exam don’t have great predictive value as to when you are going to go into labor, but it’s hard not to read into the information and thus add to the emotional roller coaster of the last weeks of labor. In addition to being No Fun, this can lead to discouragement, stress (remember that stress hormones fight your labor hormones) and a higher likelihood of consenting to procedures, such as induction, that you may not have really wanted. Many women find it better to peacefully wait it out without exams, knowing that labor will start when it’s right for the baby.
How about physical risk? Yes, there are real physical risks to vaginal exams. Although the care provider dons a sterile glove, they are not inserting it into a sterile place. We all have normal “vaginal flora” in the lower part of the vagina, which, during a vaginal exam, is pushed onto the cervix. The result? A higher risk of infection of the membranes of the amniotic sac, which is a serious complication. Studies confirm a link between vaginal exams, infection, and premature rupture of membranes**.
It’s up to you to weigh the benefits and risks of any intervention proposed during your pregnancy and birth (and really for all of your life and your child’s life for the first 18 years). When it comes to vaginal exams during pregnancy and other procedures, remember the “BRAIN” acronym: What are the Benefits, what are the Risks, what Alternatives do I have, what does my Intuition tell me, and what happens if we just do Nothing and let nature take its course?
So then, what’s the deal with vaginal exams during pregnancy? The nutshell version is that they sometimes can provide some useful information, but if there is no indication and the exam is simply being performed as a routine procedure, it may be that the benefits do not outweigh the very real risks in your individual case. If the exam is being proposed due to a particular indication, you still (and always) want to ask the BRAIN questions in order to make an informed decision.
*If external palpation leads the care provider to suspect that your baby is not head down, he or she will likely want to confirm the baby’s position via a vaginal exam or ultrasound.