Close-up of a woman clasping her bra, implying a tighter fit after pregnanacy due to postpartum rib flare.

Before I gave birth to Talia, I wore a 36 D bra.

A few days postpartum, I wandered into the little baby boutique at our community hospital where they fit nursing bras.

I was a 40 G.

If we can ignore my engorged breasts for a sec, that’s a 4 INCH increase in the diameter of my rib cage.

I was stunned.

But here’s the thing: This is yet one more thing that is SO normal but just doesn’t get discussed.

It is 100% common, normal, expected that your rib cage will get wider during pregnancy.

What Is Rib Flare?

Maybe you’ve noticed your bra is fitting tighter.

Or maybe you’ve noticed you’ve got sticky-out ribs.

Or that you can’t get your arms overhead without shoving your chest out.

This phenomenon is postpartum “rib flare”.

And it can happen in two dimensions.

1) Your whole rib cage can flare upwards as a unit, creating a hinge point in your spine.

A side-by-side image of myself demonstrating a neutral rib cage (nipples pointing forward) and a flared rib cage (nipples pointing to the ceiling).
On the left, the rib cage position is neutral. On the right, the rib cage is flared upward.

2) Your rib cage becomes WIDER.

The angle created by the lower ribs (the rib angle or infrasternal angle), hinging at the sternum becomes flatter.

Side-by-side pictures of myself outlining my lower ribs with my hands to demonstrate a narrow and wide rib cage angle.
On the left, the rib cage angle (formed at the intersection of the left and right lower ribs) is “narrow”, less than a 90 degree angle. On the right, I’m demonstrating a “wide” rib angle, greater than 90 degrees.

What Causes Flared Ribs?

As your sweet babe grows inside of you, your body needs to make space.

Just as your pelvis CHANGES SHAPE to accommodate your growing babe, so does your rib cage.

As your internal organs press upwards, the rib cage tips upward and becomes wider to accommodate the demand.

Is Rib Flare Dangerous?


Do you want to address it?

I would.

Here’s why:

4 Reasons to Address Rib Cage Flare:

Rib flaring leads to muscle imbalances and those lead to an array of body aches, pelvic floor symptoms and reduced strength.

1) Aches and pains

If the rib cage is flared UPWARD, the abdominal muscles get stuck in a “stretched” state.

And where something is stretched, something else gets compressed.

In this case, the muscles of your lumbar spine.

I’m looking at you Low Back Pain.

2) You won’t feel as strong

If the rib cage flares WIDE, the diaphragm gets caught in a stretched position as well.

The diaphragm drives the deeep core canister and the deep core cansiter is responsible for stability of your spine and creating a platform for strong movement.

If the diaphragm is rests in a stretched position, it can’t efficient charge the core cansiter and you won’t feel as strong.

3) Pesky pelvic floor symptoms

Efficient contraction of the diaphragm leverages a strong abdominal wall.

If your abs are stretched because you’re rib cage flares up, you’re diaphragm is at an additional disadvantage.

If your diaphragm’s not happy, the rest of the team (pelvic floor, abs, back extensors) are not happy either.

When your core is off it’s game, you may experience pesky pelvic floor symptoms.

This could manifest as pelvic floor dysfunction, including persistent abdominal separation, pelvic floor tightness, prolapse symptoms or incontinence.

4) It’s harder to take a good breath.

Maybe I should have led with this one??

Okay. This is all to say:

Let’s address your rib flare. And let’s not make a big ol deal out of it.

How To Fix Rib Flare After Pregnancy

There’s no one single best exercise for rib flare.

Treating rib flare is multi-factorial.

But bringing awareness to your body alignment, creating expansion in your back body and improving rib cage mobility through breathing exercises can work wonders.

1) Check in with your body alignment.

If your rib cage flares UP, you can begin to address this with intentional rib cage positioning.

Exhale your ribcage down and then relax your abs. Don’t grip your abs to hold your rib cage in position.

2) Create expansion in your back body.

Relax those compressed back muscles using (you guessed it) breathing.

Here’s my favorite:

Rock Back Breathing

3) Get really serious about your exhales.

Do you practice the Connection Breath?


Practice blowing out ALL of your air until your feel your deep abs kick on which will help pull those low ribs towards one another.

You can also try these variations:

Connection Breath With Reach

The reach will help position your rib cage down.

360 Breathing in 90/90 Position

360 breathing in 90/90 is fantastic if you know you have a bit of anterior pelvic tilt. It will help reposition your pelvis AND your rib cage.

“Ha” Breathing

The Ha Breath does a little better job of recruiting the intercostal muscles (muscles between the ribs) that draw the ribs back down and together. See how it feels!

4) Invest in strength training.

Ultimately, you need great strong (balanced!) core muscles to maintain the orientation of your rib cage and pelvis.

As you return to exercise after pregnancy, build strength from the inside out. Start with retraining your deep core and then progress to full body strength workouts. 

If you’re paying attention to your breath and body alignment during your full body workouts, you’ll continue working your core with each rep.

Can You Fix Rib Flare?

More than likely, your rib cage will eventual reset to it’s previous diameter.

But you might not reset it’s shape without a little intentional effort.

If you’d like additional guidance, you can consult a pelvic floor physical therapist or a qualified postpartum personal trainer. I offer strategy sessions and individualized personal training to address your unique postpartum concerns.

So now I’m dying to know:

Did you notice that your bra’s been fitting tighter?

Did you know they could impact your pelvic health?

And of course: Will you try these exercises? Leave a comment!

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Redmond, WA-based Seattle birth doula Laura Jawad, headshot

My mission is to make sure that having a baby is not a reason why you can’t do all the things.

Contact me with questions about exercise or pelvic health pertaining to pregnancy or postpartum. I offer customized, online pregnancy and postpartum personal training to folks locally (Seattle-area, Bellevue, Redmond, Kirkland) and beyond.

Proud Certified Prenatal & Postnatal Coach, Pregnancy & Postpartum Athleticism Coach and Postnatal Fitnesses Specialist.