Posterior Cervix: What It Means in Pregnancy & Labor

Among the whirlwind of pregnancy prep and prenatal checks, your doc might have told you that you’re sporting a posterior cervix. But what does it mean?

Does it make this whole pregnancy thing a bit more comfortable? Or tougher? And what about labor?

Don’t fret, mama — we’re here to answer this cervical conundrum, together.

In this article: 📝

What does it mean if your cervix is posterior?

Let’s briefly break down where your cervix is and what its job is: it’s at the back of your vaginal canal (you can find it yourself!), and it’s there to let sperm into your uterus and keep bacteria and (ahem) other things out.

And if you’re pregnant, it’s also keeping baby safe until they make their grand entrance into the world.

If it’s facing forward, it’s an anterior cervix. If it’s tilted to the back — yep, you guessed it — that’s a posterior cervix.

If you’re pregnant, your cervix is more likely to be posterior, until it shifts to an anterior angle for labor and birth.

Is it normal to have a posterior cervix?

Yes, it’s totally normal to have a posterior cervix — there’s nothing wrong with it at all. And usually, if you have a posterior cervix, it can mean your uterus is anterior — and vice versa.

It’s common for women to have an anterior uterus, so it could mean that it’s just as common for women have a posterior cervix, too. It could also mean that the angle between your cervix and uterine corpus (the body of your uterus) is tilted forward, too (AKA anteflexion).

But, frankly, there aren’t many studies into how many people have a posterior cervix. This could be because cervices can change position, too — especially during pregnancy — they’re pretty impressive.

Does everyone have a posterior cervix?

Nope, not every woman has a posterior cervix. We’re not sure exactly how many people have posterior cervices, but they are quite common — so if you have one, you’re certainly not alone!

Is a posterior cervix bad?

No, having a posterior cervix isn't inherently "bad" — and it’s not caused by anything you’ve done. Most of the time you can expect your posterior position to remain throughout most of your pregnancy.

It's not until closer to birth (weeks 37 or 38) that the cervix will move forward into an anterior position. If your cervix is still posterior after 38 weeks, don't panic.

There’s a chance it could make labor trickier if you’re pregnant, and having a posterior cervix at a high angle (more than 90°) could be an indicator of having an “incompetent cervix”, when paired with other factors, like a shorter cervical length.

FYI, “incompetent cervix” is a medical term we’re not keen on (and we’re not alone!) — we prefer “early cervical dilation”, which we think makes things a bit clearer without sounding as hurtful.

Is it hard to get pregnant with a posterior cervix?

There’s no evidence to suggest that having a posterior cervix could affect your fertility, no. It might make Pap smears and other exams a bit more uncomfortable, according to our Peanut mamas, which could be because it’s tucked a bit further back, but for most women, it shouldn’t cause any discomfort.

A posterior cervix could be linked to “cervical incompetence”, with other indicators, like cervical length and funneling, which has also been linked to pregnancy loss, but, by itself, a posterior cervix shouldn’t make it harder for you to conceive.

Can you go into labor with a posterior cervix?

Yes, you can go into labor with a posterior cervix — it’s likely to move to an anterior angle before active labor, anyway. So if you’re around 37 weeks pregnant and you’ve been told that you have a posterior cervix, it’s likely that labor won’t be starting for a little while.

This is because, with a posterior cervix, it’s behind baby’s head — for labor, it’ll ideally be in front of baby’s head, to make their exit route a bit easier to get to. It tends to move from posterior to anterior as a precursor to labor.

How quickly can a cervix change from posterior to anterior?

Well, there’s no specific timeframe for how long it takes your cervical angle to shift from posterior to anterior in your third trimester. It tends to happen at about 37 or 38 weeks, and can happen pretty quickly — sometimes between prenatal checks.

It’ll likely happen while your cervix also gets softer and starts to efface — it’s got a lot of work to do right now!

Is it harder to dilate with a posterior cervix?

Potentially, yes, dilation could be harder with a posterior cervix. Why? Well, it’s all to do with the stiffness of your cervix.

According to this study, using a special technique called shear wave speed (or SWS), they found that posterior cervices are “stiffer” than anterior cervices. This could make dilation a bit slower if you have a posterior cervix during labor.

It might be that your labor takes longer with a posterior cervix, compared to an anterior one.

Can I be induced with a posterior cervix?

Yes, you can be induced if you have a posterior cervix. Induction of labor is when your healthcare provider “triggers” labor — a way of getting the whole birth process started.

It’s usually only done if you’re past your due date or if there are other medical reasons, like concern for yours or baby’s health if the pregnancy continues. There’s some evidence that seems to suggest that having a posterior cervical angle could mean that your body’s response to an induction of labor is more successful.

But does having a posterior cervix mean you’re more likely to have your labor induced? Well, we’re not sure.

This study suggests that looking at the position of your cervix alone isn’t an accurate way of predicting whether you’ll need to be induced or if you’re more likely to have a C-section.

(Actually, this study, and this one, seem to suggest that having a posterior cervical angle could mean that you’re more likely to have a vaginal delivery.)

But, combined with a few other factors, like your cervical length, how many babies you’re expecting, and your Bishop score (which looks at how much you’re dilated and effaced, baby’s position, and the softness of your cervix), your doc can get a better idea of whether you’re more likely to be induced. And, interestingly, this study suggests that having an anterior cervix could mean that your chances of preterm birth are higher.

It’s worth discussing with your healthcare provider whether you’re more likely to be induced if you have a posterior cervix, they’ll be able to give you more info based on your specific circumstances.

Can you have a sweep with a posterior cervix?

Yes, you can have a membrane sweep if you have a posterior cervix. A membrane sweep is something your doctor can do to encourage labor to start — where they separate the membranes that connect your amniotic sac (with baby inside) to your cervix (and your uterus, but they don’t separate all the membranes).

But, as Dr Gary Sykes says, it could be more painful if you have a posterior cervix. If you or your doctor suggest a membrane sweep, it’s worth discussing the potential discomfort and the next best steps if you’re not able to carry on with it.

How can I encourage my cervix to move forward?

If you’re keen to get labor kick-started, but your cervix is still posterior, the best thing you can do is wait and keep checking in with your healthcare provider. It might be that induction is your best port of call, but your doctor will be able to advise you on that.

There are some things you can do that could help encourage your posterior cervix into an anterior position and get labor started, but they’re not guaranteed:

• Get on all fours! According to our Peanut mamas, they were advised to get on the floor and crawl about on their hands and knees, which could help shift your cervix to an anterior angle.
• Pelvic tilts to strengthen your pelvic floor muscles and encourage baby’s head to get to the right position, too.
• Use a birthing ball, especially in the first stage of labor, as it could encourage dilation, effacement, baby’s optimal position, and contractions.

So if you have a posterior cervix, don’t worry — it’s totally normal. In fact, if you’re pregnant, it’s expected for your cervix to be angled more to the back. It’ll move to an anterior position for labor, when baby’s ready to meet you for the first time.

But if you’re at all concerned about it, or anything to do with your health, always ask your doctor. There’s no such thing as a silly question when it comes to your health — you are a priority. As you approach the big day, remember to trust your instincts and advocate for yourself.

Your body is incredibly resilient, and you have the strength to bring your babe into the world. So take a deep breath, and know that you’re not alone, mama.

And if you want to talk to other women who have been there, you’re always welcome to join us on Peanut.