Your ribs really did move. Here is what that means.
Rib flare is one of the least explained changes after pregnancy, and it sits right at the centre of how your deep core works.
Quick answer
Rib flare is when your lower front ribs sit lifted and turned outwards instead of stacked over your pelvis. During pregnancy the lower ribcage widens to make room for a growing uterus, and after birth that position often does not reset on its own, especially if your breathing pattern changed to cope.
It is a position and a habit, not damage. It usually responds to restoring a full exhale and retraining the deep core in a stacked rib position, rather than to stretching, sucking in or bracing harder. Results vary from mum to mum, and persistent pain or leaking is a reason to see a women's health physiotherapist.
of women had a diastasis recti separation at 6 weeks postpartum (Sperstad et al., BJSM, 2016)
still had a separation at 12 months postpartum in the same study
in the rib position routine below, none of which need equipment
What rib flare actually is
Run your fingers up from your belly button until you find the bony edge on each side. That is your lower ribcage. In a neutral position those lower ribs sit softly down and back, roughly stacked above your pelvis, so your diaphragm at the top and your pelvic floor at the bottom face each other like two ends of a canister.
With rib flare, that bottom edge is lifted and turned out. You may see it as a visible ridge or a triangular gap below your chest, feel it as ribs that stick out when you lie on your back, or notice your bra band sitting differently than it used to. Many mums describe their ribcage as simply feeling wider, and they are not imagining it.
Crucially, rib flare is a description of position, not a diagnosis. It is not a tear, a separation or an injury, and having it does not mean anything is broken.
Why pregnancy changes the ribcage
As the uterus grows it needs room, and the lower ribcage is one of the places the body finds it. The ribs move up and out, the diaphragm gets pushed higher, and breathing shifts upwards into the chest because there is less space to breathe down into. The NHS notes that many of the physical changes of pregnancy take months rather than weeks to settle after birth.
Once the baby is out, the mechanical reason for the flare disappears, but the pattern often stays. Months of shallow upper chest breathing become the default. Add feeding posture, carrying a baby on one hip, and the very common instinct to hold the stomach in, and the ribs have no particular reason to come back down on their own.
That matters because rib position drives pressure. When the ribs stay flared, the diaphragm and the pelvic floor no longer line up, so each breath sends pressure forwards into the abdominal wall rather than managing it evenly. Our explainer on intra-abdominal pressure covers that mechanism in detail, and it is the reason rib flare so often travels alongside coning or doming along the midline.
Rib flare, diastasis recti or a normal postpartum belly?
These get mixed up constantly, partly because they can all be present at once. They are different things.
| What you notice | Where it is | What usually helps | |
|---|---|---|---|
| Rib flare | Lower ribs lifted or turned out, wider ribcage, ridge below the chest | Bony rib edge, above the waist | Restoring the exhale, stacking ribs over pelvis, deep core retraining |
| Diastasis recti | A gap or soft valley along the midline, sometimes doming when you sit up | Along the linea alba, usually around the navel | Graded deep core loading and pressure management over months |
| Normal postpartum belly | Softness, fullness that changes through the day | Lower abdomen | Time, sleep where possible, gentle progressive activity |
If you are unsure which you are looking at, our at home self check walks through testing the midline specifically, and what the linea alba is explains the tissue involved.
How to check your own rib position
Lie on your back with your knees bent and feet flat. Rest your hands so your thumbs sit on your lower ribs and your fingers spread across the front. Breathe normally for a few breaths and notice two things: whether the ribs under your hands stay lifted even as you breathe out, and whether the space between the two rib edges feels wide and open rather than softening down. If the ribs never travel down on the exhale, that is the pattern the steps below are aimed at.
Step 1: Rebuild the exhale
Most rib flare work fails because it starts with position instead of breath. Lying on your back, inhale gently through the nose and let the lower ribs widen sideways rather than lifting. Then exhale slowly through pursed lips, as if fogging a mirror, and let the exhale run all the way to the end. That final part of the exhale is what draws the ribs down. Five to eight breaths is plenty. If you have never done this, our guide to deep core breathing is the natural place to start.
Step 2: Stack the ribs over the pelvis
Still on your back, exhale fully and feel the lower ribs settle down towards the floor without tucking your tailbone or flattening your spine hard into the ground. You are aiming for the sensation of the ribcage sitting over the pelvis rather than in front of it. Hold that stacked position for two or three easy breaths, then release. The goal is a position you can breathe in, not a brace you have to hold.
Step 3: Load the deep core in that position
Only once the ribs will come down do you add work. From the stacked position, exhale and slide one heel along the floor until the leg is nearly straight, then bring it back. Swap sides. Watch two things: the ribs should not pop back up, and there should be no doming along your midline. If either happens, the leg is going too far. This is the deep abdominal wall learning to work in a good position, which is exactly the job of the transverse abdominis.
Step 4: Take it into daily life
Positions you hold for hours beat exercises you do for minutes. While feeding, aim for ribs down and shoulders relaxed rather than a stiff upright hold. When lifting the car seat or the pram, exhale as you lift instead of holding your breath. When standing, notice whether you have parked your weight into one hip. Our piece on postpartum posture covers the everyday version of this, and because the pelvic floor is the other end of the same system, how the pelvic floor and diastasis recti connect is worth reading alongside it.
The short version
Rib flare is a position, not a problem to be fixed by force. Stretching the ribs, sucking the stomach in or wearing something tight does not teach the ribcage where to sit. A full exhale, a stacked position and gradual deep core loading does, and it also improves how your body handles pressure day to day. Progress here is measured in how you move and feel, not in how your ribs photograph, and it varies from mum to mum.
The whole system, in one plan
Rib position, breathing, deep core and pelvic floor are one system, and working on them together is what makes the difference. The Complete Postpartum Body Reset bundles our full set of guides for 50 US dollars, paid once, yours to keep. Use code GLOW20 for 20 percent off. Individual guides start at 15 US dollars if you would rather begin with one.
Frequently asked questions
Does rib flare go away on its own after pregnancy?
Sometimes it settles as posture, breathing and abdominal strength recover in the months after birth. Often it does not fully resolve without attention, because the shallow upper chest breathing pattern learned during pregnancy tends to persist. Retraining the exhale is usually what changes it. Results vary from mum to mum.
Is rib flare the same as diastasis recti?
No. Rib flare describes the position of your lower ribs, while diastasis recti describes a widening of the connective tissue along your midline. They frequently occur together because both are linked to how pressure is managed inside the abdomen, but one is not the other and they are assessed differently.
Will a belly band or waist trainer fix rib flare?
Compression garments can feel supportive and some mums find them comfortable in early recovery, but squeezing the outside of the ribcage does not teach the diaphragm and deep abdominal wall to work together. Position that is held by a garment tends to disappear when the garment comes off.
Can I do this if I had a caesarean?
Breathing work is generally among the earliest things suitable after any birth, including caesarean, but timing depends on your own healing and your care provider's advice. Clear it with your GP, midwife or physiotherapist first, and stop anything that causes pain around your scar.
When should I see a women's health physiotherapist?
Book an appointment if you have ongoing pain in your back, ribs or pelvis, leaking urine, a feeling of heaviness or dragging in the pelvis, or a bulge along your midline that is not improving. A physiotherapist can assess rib position, breathing and the pelvic floor together, which is far more useful than guessing from a mirror.
Sources: Sperstad et al., British Journal of Sports Medicine, 2016; NHS, Your body after birth; ACOG, Exercise After Pregnancy.
This article is general education, not medical advice. Results vary from mum to mum. If you have pain, leaking, a feeling of heaviness in the pelvis, or a bulge along your midline, please speak to your GP, midwife or a women's health physiotherapist before starting or continuing any exercise programme.