One of the students working with me on L&D recently complained that she wasn't getting…
Pregnant women, should you check your own cervix at home?
Every so often, I have a patient conversation that includes the phrase “Well, I checked my cervix at home, and…” Buckle up, boys and girls, that means this is going to be an interesting conversation.
Overall, people who check their cervix at home (or have their spouse check it) fall into one of two camps.
The first group aren’t so bad; they are people who live REALLY far from a hospital (over an hour) and, in an act of desperation as they are trying to decide whether to come in, they check their cervix or have their partner check their cervix. They read about it on the internet and were hoping to avoid an unnecessary multi-hour drive in the middle of the night.
The second group are, well, less fun. They are the folks who don’t trust the doctors, who think that they know better and want to prove to me that they really are in labor. They want to debate their cervical exam with me.
One particularly memorable patient, who had had three previous vaginal deliveries, used to come to our labor and delivery triage a few times a week. She had terrible round ligament pain and always thought she was in labor. As someone who had had vaginal deliveries before, her cervix was about 3cm dilated the first time I saw her, at approximately 33 weeks. It stayed the same 3cm right up until she came in at 39 weeks for an induction. Her husband used to check her cervix at home and would insist that it had changed. I don’t remember anymore what he did for a living, but he was not in the healthcare field. “Well, I think it’s more dilated today than it was,” he would say. And I would have to tell him that while her cervix is soft and stretchy, it was still 3cm. He hated it. He got so upset every time that happened. He had packed up and rushed to the hospital thinking it was “go time” only to have me tell him that he was wrong, that my exam was better than his.
Anyone who performs cervical exams for a living has performed at least hundreds of cervical exams, more likely thousands or tens of thousands. I performed at least two hundred cervical exams in my first month as an intern. Most of these exams were double-checked by a more senior provider, allowing me to hone my skills. My fingers have been “calibrated” to agree with the rest of the physicians that I work with. I can be confident that if I check your cervix and call you 3cm, my colleague is not going to call you 6cm unless there has been a true change. This sort of accuracy and reproducibility takes practice and training, though. Checking your cervix a few times during your pregnancy is not enough to get an accurate assessment of cervical dilation.
In all honesty, during the first ten or so cervical exams that most clinicians perform (particularly with patients who are not in labor or in early labor, at 3cm dilation or less), it can be very difficult to even find the cervix. Add in that the cervix can be extremely soft and stretchy in late pregnancy and in labor, and you can get all kinds of inaccuracies. I work with rotating emergency medicine residents who need to learn how to check a cervix. Starting out, sometimes they miss the cervix completely and call someone closed who is really 5cm, or they call someone 7cm who is really only 4cm. Those differences matter!
Like anything else in medicine, cervical exams in labor are a learned skill.
I should mention, at this point, that cervical exams in labor are very different from exams that are used, say, to track ovulation. Some people use the sympto-thermal method of cycle tracking, in which they assess cervical consistency on a regular basis. They are looking for subjective changes in their own cervix’s position and consistency. Checking cervical consistency for fertility tracking is much easier measuring cervical dilation and effacement in a way that is accurate and reproducible.
Even cervical exams by providers have fallen out of favor before the onset of labor. Why? Because they don’t change management. Some patients walk around 3cm dilated for weeks, and others are closed and long until 24 hours before delivery. Knowing what your cervix is doing before you present with concern for labor does not change our management, and it has risks!
The vagina is normally colonized – it has healthy bacteria, just like the gut. The uterus, on the other hand, is supposed to be sterile. In the same way that the healthy bacteria from the gut can cause a problem if they make it into the urinary tract, the healthy bacteria from the vagina can cause trouble if they get into the uterus. Concerns have been raised that cervical exams can lead to mild inflammation of the fetal membranes, weakening the membranes and potentially leading to infection of the fetal membranes and amniotic fluid, even before the onset of labor. It’s mostly a theoretical risk, but if there is no benefit, why accept even a theoretical risk?
So, should you check your cervix at home? I didn’t when I was pregnant, and I don’t recommend that you do it, either.