Your aching back and your tummy gap may be part of the same story
The honest evidence on whether diastasis recti causes lower back pain, and what actually eases it.
Quick answer
Diastasis recti and lower back pain often turn up together after birth, but the research does not show that the gap itself causes the pain. In fact, Sperstad et al. (British Journal of Sports Medicine, 2016) found women with diastasis recti were no more likely to report lumbopelvic pain than women without it. What usually drives postpartum back ache is a deep core system that has stopped coordinating properly, along with posture changes, feeding positions and carrying a growing baby. The good news is that the same gentle retraining that helps a diastasis, breath-led deep core work, glute strength and better daily positioning, is also what tends to settle the back.
Why so many mums have both at once
If you have been told you have a tummy gap and your lower back has been grumbling since your baby arrived, it is very reasonable to assume one caused the other. Plenty of websites will tell you exactly that. The picture is more interesting, and more useful, than a simple cause and effect.
Pregnancy changes the abdominal wall considerably. The linea alba, the connective tissue seam running down the centre of your stomach, softens and widens to make room for your growing baby. That is diastasis recti, and Cleveland Clinic describes it as a normal adaptation of pregnancy rather than an injury. At the same time, your centre of gravity shifts forward, your ribcage flares, your pelvis tilts and your deep stabilising muscles work in an unfamiliar pattern for months.
Then the baby arrives and the demands change again. You feed in awkward positions, you lift a car seat that gets heavier every week, you sleep badly, and you probably do not have a spare half hour to stretch. Your back is responding to all of that, not just to the width of your gap.
of women still had diastasis recti at six weeks postpartum (Sperstad et al., British Journal of Sports Medicine, 2016)
at six months postpartum in the same cohort (Sperstad et al., 2016)
still present at twelve months postpartum (Sperstad et al., 2016)
What the research actually says about the link
This is where it pays to be precise. The Sperstad study followed a large group of first-time mothers and looked specifically at whether diastasis recti was associated with lumbopelvic pain. It was not. Women with a separation reported back and pelvic pain at similar rates to women without one.
That finding surprises people, because the mechanical logic feels so obvious. But a gap in the connective tissue is a measurement, not a diagnosis of weakness. Two mums can have an identical two-finger gap and completely different experiences: one has a firm, responsive core that generates tension across the midline, the other has a soft, unresponsive one. The measurement does not capture that difference, and it is that difference which tends to matter for how your back feels.
So the honest position is this. A wide gap on its own does not predict back pain. Poor deep core coordination, which frequently accompanies a diastasis, plausibly does contribute. That is a meaningful distinction, because it changes what you should spend your limited time on.
The real drivers of postpartum lower back ache
Your deep core has gone quiet
Your transverse abdominis and pelvic floor are meant to fire slightly ahead of movement to stabilise your spine. After pregnancy and birth that anticipatory timing is often disrupted. Your back muscles then take on stabilising work they were never designed to do all day, and they let you know about it.
Feeding and carrying positions
Eight to twelve feeds a day, often hunched forward, adds up fast. Add carrying your baby on one hip, and one side of your pelvis and lower back does a disproportionate share of the work.
Weak or sleepy glutes
When your glutes are not contributing, your lower back compensates during every lift, stand and stair climb. This is one of the most overlooked contributors, and one of the most fixable.
Sleep, stress and general depletion
The NHS notes that back pain is common in the months after birth and that gentle, progressive activity generally helps. Exhaustion lowers your tolerance for discomfort and makes you move in stiffer, more guarded ways, which itself feeds the cycle.
What tends to help, and what does not
| Approach | Effect on the gap | Effect on back pain | Worth your time? |
|---|---|---|---|
| Breath-led deep core work | Builds tension across the midline | Restores stabilising timing | Yes, start here |
| Glute and hip strengthening | Indirect support | Often the biggest single change | Yes, badly underrated |
| Position and feeding tweaks | Reduces daily strain | Immediate relief for many mums | Yes, free and fast |
| Crunches and sit-ups | Can increase doming | Frequently aggravates | Not yet |
| Belly binders worn all day | No lasting structural change | Short-term comfort only | Optional, short term |
| Rest and waiting it out | Little change after 8 weeks | Often prolongs it | No |
The pattern is consistent. Passive approaches feel supportive in the moment but do not retrain anything. If you are curious about why the classic ab exercises backfire, we covered that in the trouble with crunches after birth, and there is a fuller breakdown of safe alternatives in which postpartum core exercises are genuinely safe right now.
Five things to change this week
1. Breathe into your ribs, not your shoulders
Lie on your back, knees bent. Inhale and let your lower ribs widen sideways. Exhale slowly and feel a gentle lift through your pelvic floor and a soft drawing-in low across your belly. Five minutes daily. This is the foundation everything else sits on.
2. Exhale on effort
Every time you lift your baby, stand from the sofa or pick up the car seat, breathe out as you do it. This single habit recruits your deep core hundreds of times a day without adding a workout.
3. Wake your glutes up
Glute bridges, side-lying leg lifts and slow sit-to-stands. Two or three short sessions a week is enough to start shifting load off your lower back.
4. Fix your feeding setup
Bring the baby to your breast or bottle rather than curling down to them. A cushion under your arm and a rolled towel behind your lower back changes hours of your day.
5. Stop testing your gap every morning
Checking daily tells you nothing useful and keeps your attention on a number instead of on function. Once a month is plenty. If you want to know what a meaningful improvement looks like, this guide to knowing when a diastasis has actually healed sets sensible expectations.
The bottom line
Do not chase the gap and hope your back follows. Train the system: breath, deep core, glutes, and the way you move through an ordinary day with a baby. Most mums who do this consistently notice their back settling well before the measurement changes, and that is exactly the order you should expect. Results vary from mum to mum.
When to see someone in person
Self-directed work suits most mums, but book an appointment with your GP, midwife or a women's health physiotherapist if you have pain radiating down your leg, numbness or tingling, pain that wakes you at night, any loss of bladder or bowel control, or pain that is getting worse rather than better over several weeks. A physio can assess your pelvic floor and abdominal wall directly, which no article can do. If you are weighing up that decision, our comparison of at-home guides, trainers and physios lays out the costs and trade-offs plainly.
How long does it take?
Most mums who train consistently notice their back feeling more supported within four to eight weeks, often before any visible change to the belly. Connective tissue remodelling is slower, which is why the twelve-month figures above still show a third of women with a measurable separation. That is not failure, it is biology. The evidence on closing a diastasis without surgery goes deeper on realistic timelines, and if this is not your first baby, recovery after a second or third birth explains why the process often takes longer.
Want the whole sequence laid out for you?
Core Reconnect walks you through the breath work, deep core progressions and glute strengthening in the order they actually work, designed for ten minutes a day with a baby nearby. It is a one-time purchase with no subscription and no app, which is why mums often choose it over programs like MUTU that bill monthly. Use code GLOW20 for 20% off.
Frequently asked questions
Can diastasis recti cause lower back pain?
Not directly, based on current evidence. Sperstad et al. (British Journal of Sports Medicine, 2016) found no association between diastasis recti and lumbopelvic pain. The deep core weakness that often accompanies a separation is the more likely contributor, which is why retraining coordination helps more than focusing on the gap width.
Will closing my gap make my back pain go away?
Not necessarily, and waiting for the gap to close before addressing your back is the wrong order. Most mums report their back settling weeks or months before the measurement changes meaningfully, because function improves faster than connective tissue remodels.
Are planks safe if I have both a diastasis and back pain?
Usually not as a starting point. Planks demand a level of core tension most mums do not yet have, and the compensation pattern often loads the lower back. Build breath-led deep core control first, then progress to modified versions on your knees or against a wall.
Should I wear a support belt for my back?
Short periods can feel genuinely helpful, particularly in the early weeks. All-day use is a different matter, as it can reduce how much your own muscles are asked to do. Treat it as temporary comfort while you build strength, not as the strategy itself.
How soon after birth can I start core work for back pain?
Gentle breath work and pelvic floor connection can typically begin within days for a straightforward vaginal birth, and a little later after a caesarean. ACOG advises resuming physical activity gradually once it is medically safe for you, so use your six-week check as the point to confirm with your own clinician.
diastasis recti back pain postpartum lower back pain deep core postpartum
Sources: Sperstad JB et al., "Diastasis recti abdominis during pregnancy and 12 months after childbirth," British Journal of Sports Medicine, 2016; NHS guidance on postnatal recovery and back pain; American College of Obstetricians and Gynecologists (ACOG) guidance on physical activity after pregnancy; Cleveland Clinic overview of diastasis recti.
This article is general education, not medical advice, and Mumma Glow is not affiliated with any of the programs or organisations named. Results vary from mum to mum. Please speak with your GP, midwife or a women's health physiotherapist about your own recovery, particularly if you have pain that is severe, worsening, or accompanied by numbness or changes in bladder or bowel control.