The Miles Circuit: Why Baby’s Position Matters at the End of Pregnancy

When we start talking about preparing for labor in the final weeks of pregnancy, one incredibly important piece of the conversation is baby’s position.

Getting baby head down is an important first step toward a vaginal birth, but head down isn’t necessarily the whole story.

How baby is positioned within the pelvis can make a BIG difference in how labor unfolds.

This is one of the reasons the Miles Circuit can be such a helpful tool during the third trimester and even during labor. It is a series of three positions designed to create space within the pelvis and encourage baby toward a more favorable position for birth.

Head Down Is the First Step, But Position Matters Too

When a baby is head down, this is called a cephalic or vertex presentation. This is typically the presentation we want to see when preparing for a vaginal delivery.

But there are several different ways a head-down baby can be positioned.

Ideally, we want baby in an occiput anterior (OA) position, meaning baby’s head is down and the back of baby’s head is generally toward the front of the birthing person’s body.

In this position, baby is often able to tuck their chin and navigate through the pelvis efficiently.

A baby can also be head down but occiput posterior (OP).

You may have heard this called:

“Sunny side up”

or

“Stargazing” / “staring at the stars.”

In an OP position, baby’s head is still down, but the back of baby’s head is toward the birthing person’s back.

And that distinction can matter!

Why Can a Posterior Baby Make Labor More Challenging?

Many posterior babies rotate beautifully during labor, and babies absolutely CAN be born vaginally while posterior.

However, when a baby remains persistently OP, research has associated that position with longer labor, a longer pushing stage, increased need for Pitocin/oxytocin augmentation, assisted vaginal delivery, and cesarean delivery compared

with babies delivering in an anterior position.

OP positioning is also commonly associated with the infamous back labor.

Instead of primarily feeling contractions wrapping around the abdomen, someone experiencing back labor may feel significant pressure or pain through the lower back, sometimes even between contractions.

The American College of Obstetricians and Gynecologists (ACOG) explains that back labor can occur from pressure of baby’s head against the lower back.

This is one reason fetal positioning deserves attention as we approach birth.

Sometimes when labor isn’t progressing the way we expect, the question isn’t simply:

“Why isn’t the cervix dilating?”

Sometimes we also need to ask:

“How is baby trying to enter and move through the pelvis?”

Baby Has to Do More Than Come Down. Baby Has to Rotate.

Birth is not simply baby moving straight down through an open tunnel.

The pelvis has different dimensions at the inlet, mid-pelvis, and outlet, and baby has to navigate those changing spaces while descending.

Baby rotates.

Baby flexes.

Baby’s head molds.

Baby finds space.

This is why movement and positioning during labor aren’t just about comfort. They can be tools.

If baby’s head isn’t well applied to the cervix, or baby is having difficulty rotating or descending, labor may become longer or appear to stall.

Persistent fetal malposition has been associated with a longer second stage of labor and an increased likelihood of operative vaginal or cesarean delivery.

That doesn’t mean an OP baby automatically equals a difficult birth. Far from it! Many babies rotate during labor, and many posterior babies are born vaginally.

It simply means position is one piece of the birth puzzle worth paying attention to.

So, What Is the Miles Circuit?

The Miles Circuit is a sequence of three positions that takes approximately 90 minutes to complete.

The circuit was developed from positioning techniques used in the birth community and is intended to create space for baby to reposition and settle into the pelvis.

The three basic parts are:

1. Open knee-chest position

2. Exaggerated side-lying position

3. Upright movement, such as lunging, walking, or using asymmetrical positions

Each position is generally held for 30 minutes.

The goal isn’t to physically “make” baby turn.

Instead, we are using gravity, movement, pelvic space, and maternal positioning to give baby an opportunity to find a favorable position.

The official Miles Circuit website provides detailed instructions for performing the circuit and explains how it can be used both prenatally and during labor when baby may benefit from improved alignment.

Why Practice the Miles Circuit BEFORE Labor?

We don’t want the first time someone hears the words “Miles Circuit” to be when they’re exhausted and already hours into labor!

Practicing the Miles Circuit toward the end of the third trimester allows the birthing person and their partner to become familiar with the positions ahead of time.

Then, if the Miles Circuit or similar fetal positioning techniques become useful during early labor, the positions aren’t completely foreign.

You’ve done them.

Your partner recognizes them.

Your body knows the positions.

And you can get to work.

It can also be a wonderful way to intentionally spend some time focusing on optimal fetal positioning as the due date approaches.

And Here’s Another Reason Position and Engagement Matter: Spontaneous Labor

Another reason we focus on fetal positioning toward the end of pregnancy is that we don’t just want baby head down. We want baby to have the opportunity to become well aligned and engaged in the pelvis, with their head applying good, consistent pressure to the cervix.

Why does that matter?

Because baby’s head and the cervix actually work together during labor.

As baby descends and places pressure on the cervix, that stretching helps activate what is known as the Ferguson reflex. Cervical pressure sends signals that promote the release of oxytocin, which strengthens uterine contractions. Those contractions encourage baby farther downward, creating additional cervical pressure and continuing that positive feedback loop.

Baby presses on the cervix → oxytocin supports stronger contractions → contractions encourage baby downward → baby creates more pressure on the cervix.

This is one of the physiological processes that helps labor progress once it is underway.

So, especially as we approach the final weeks of pregnancy, we want to give baby every opportunity to become head down, well aligned, and nicely engaged against the cervix.

Does doing the Miles Circuit guarantee spontaneous labor? No. There is no evidence showing that the Miles Circuit itself starts labor, and the exact process that triggers spontaneous labor is much more complex than fetal position alone.

However, the Miles Circuit can help create space and opportunity for baby to settle deeper into the pelvis and find a favorable position. When we are hoping for spontaneous labor, having baby well positioned and engaged can help support the natural mechanics and hormonal feedback we want in place as the body prepares for birth.

This is why “baby is head down!” is wonderful news, but it isn’t necessarily the end of the positioning conversation.

Head down is the first step. Head down, well positioned, engaged, and applying pressure where we want it? Even better.

When we think about preparing for spontaneous labor and vaginal birth, we are looking at the whole picture: baby’s position, engagement, cervical readiness, hormones, movement, gravity, and all of the incredible physiological pieces that eventually come together for birth.

Can the Miles Circuit Prevent a Sunny Side Up Baby?

This is where it’s important to separate what is commonly seen in birth work from what research has actually proven.

There isn’t strong scientific evidence showing that doing the Miles Circuit during pregnancy will definitively prevent an OP baby or guarantee that a baby rotates into an anterior position.

And we never want to promise that one exercise can guarantee an easier labor or vaginal birth.

Babies have opinions too!

However, maternal positioning and movement are commonly used during labor to encourage rotation and descent, and there is research supporting the role of maternal positioning and manual rotation in addressing fetal malposition.

So, it can be helpful to think about the Miles Circuit as another tool in our birth-preparation toolbox, not a magic trick.

We are creating space and opportunity.

Baby still gets a vote.

Why We May Pull Out the Miles Circuit During Labor

The Miles Circuit isn’t only something to practice during pregnancy.

It can also become a helpful tool during labor, particularly when:

• Baby appears to be posterior or otherwise mispositioned

• There is significant back labor

• Contractions have become inconsistent

• Labor seems to have slowed or stalled

• Baby isn’t descending as expected

• We want to encourage rotation before pushing

• We need productive positioning while also conserving energy

This is also where having a birth team that understands fetal positioning, pelvic anatomy, and movement during labor can be incredibly valuable.

Sometimes we need rest.

Sometimes we need movement.

Sometimes we need an asymmetrical position.

Sometimes we need to create space at the top of the pelvis.

Sometimes we need to create space lower in the pelvis.

There isn’t one “perfect birth position” for every person or every stage of labor.

We follow what the body AND baby are telling us.

Preparing for Birth Is About More Than Getting Baby Head Down

Toward the end of pregnancy, there is so much focus on dilation, due dates, and whether baby has “dropped.”

But there is a bigger picture.

Head down is step one.

From there, we can think about baby’s alignment, engagement, flexion, rotation, and descent.

Does doing the Miles Circuit guarantee a short labor?

No.

Does an anterior baby guarantee an uncomplicated vaginal delivery?

No.

Does a posterior baby mean you’re destined for back labor, failure to progress, or a cesarean?

Absolutely not.

Birth has far too many variables for any of those promises.

But understanding optimal fetal positioning gives us more tools to work with during the final weeks of pregnancy and throughout labor.

So when you start hearing about the Miles Circuit, Spinning Babies, inversions, lunges, peanut balls, side-lying releases, and all the other positions that may come into play during birth preparation and labor, there is a reason behind them.

We aren’t simply trying to get baby down.

We’re creating space for baby to engage, rotate, descend, and navigate the pelvis as efficiently as possible.

Because baby has a job in labor, too!

Want more hands-on preparation for labor? Explore my childbirth education classes and doula support.

Helpful Resources & Further Reading

The Miles Circuit: The official Miles Circuit website explains the circuit, when it may be useful, and how to perform each of the three positions.

American College of Obstetricians and Gynecologists (ACOG): Information about back labor, fetal positioning, and evidence-based labor management.

National Library of Medicine / PubMed: Research examining occiput posterior fetal positioning, labor outcomes, fetal rotation, and maternal positioning.

Spinning Babies: Educational resources and visual guides for understanding fetal positioning, posterior babies, pelvic anatomy, and creating space for fetal rotation.

MedlinePlus: Patient-friendly information about fetal presentation and positioning during childbirth.

This information is intended for general pregnancy and childbirth education and is not a substitute for individualized medical advice. Always discuss exercises and positioning with your maternity care provider, particularly if you have pregnancy complications, activity restrictions, bleeding, placenta concerns, ruptured membranes, or have been advised to limit activity.