Abdominal Separation After Pregnancy: What It Actually Is and How to Rebuild It

What Diastasis Recti Actually Is

Diastasis recti abdominis (DRA) is the widening of the linea alba — the fibrous connective tissue that runs down the centre of your rectus abdominis (the 'six pack' muscles). During pregnancy, the growing uterus pushes against the abdominal wall and the hormonal environment (particularly relaxin and progesterone) softens and stretches the connective tissue. This is a normal physiological adaptation that allows the abdomen to expand.

After birth, this tissue should gradually regain tension and the gap should narrow. In many women — research suggests up to 65-70% at 6 weeks postpartum — it doesn't fully return to its pre-pregnancy state. The gap remains wider than normal, and the connective tissue may feel weak or thin when you press on it.

This is diastasis recti. It's not a muscle tear. It's not a failure. It's a documented, common outcome of pregnancy that responds well to the right rehabilitation approach — and responds poorly to the wrong exercises.

The Signs You Might Have It

The most common signs of diastasis recti:

A visible gap or doming along the midline of your abdomen when you contract your abs — this might appear as a ridge running vertically from your sternum to your belly button, or as a distinct tenting when you try to sit up from lying down.

Lower back pain is frequently associated with diastasis. When the deep core can't generate adequate intra-abdominal pressure (because the abdominal wall is too stretched to form a competent cylinder), more load transfers to the lumbar spine. Many women with moderate-to-severe diastasis experience persistent lower back pain.

A feeling of core heaviness or 'something not being right' in your abdomen during everyday activities — coughing, laughing, lifting the baby, getting out of bed.

The gap can be at the belly button level, above it, below it, or in all three locations. Width and location affect both symptoms and prognosis.

How to Check Yourself

Here's a simple self-assessment you can do at home — though it's not a substitute for a professional evaluation:

Lie on your back with knees bent and feet flat on the floor. Place one hand behind your head (to support your neck) and the other fingers flat on your abdomen, palm down, with fingers pointing toward your toes. Position your fingers across the midline, at the level of your belly button.

Gently lift your head and shoulders off the floor — just enough to feel your abs contract. As you do this, press gently downward with your fingers. You're feeling for the space between the two sides of your rectus abdominis.

Note how many fingers' width fit in the gap, and whether you feel a noticeable 'dip' or tensionless area at the midline. Repeat at above and below the belly button.

A gap of 2 finger-widths or less at any point is generally considered within normal range. A gap of 2-3 finger-widths may indicate mild-to-moderate diastasis. More than 3 finger-widths suggests more significant separation.

Also note whether the tissue feels taut and supportive under your fingers, or whether it feels soft and giving. Tension is more important than the exact number of finger-widths.

The Exercises That Make It Worse

This is where most postnatal advice gets it wrong. Standard ab exercises are often counterproductive with diastasis:

Traditional crunches and sit-ups are the biggest offenders. They flex the spine against gravity while the abdominal wall is under load from intra-abdominal pressure — exactly the combination that widens the gap at the midline. Any exercise that causes doming or coning of the abdomen is a signal to stop.

Traditional planks (especially long-held or broken-plank variations) can also be counterproductive if they cause doming or if the core isn't ready for the sustained intra-abdominal pressure they create.

Leg lowering exercises — lying on your back and lowering straight legs — place enormous demand on the deep core before it's ready, and commonly cause doming.

Double-leg raises, bicycle crunches, and Ab Rollers or similar devices are all high-risk for worsening abdominal separation in the early-to-mid stages of recovery.

The common thread: any exercise that makes your abdomen dome, ridge, or tent at the midline is telling you the pressure is exceeding what your tissue can currently manage. That's feedback, not failure.

The Rebuild: A Phased Approach

Rehabilitation of diastasis recti follows a clear progression — and the foundation matters more than the advanced exercises.

Phase 1: Breathing and deep core activation (weeks 0-6+, depending on birth) The starting point is learning to coordinate your diaphragm with your deep core and pelvic floor. The standard cue is: breathe in, let your ribs expand laterally and your belly soften; breathe out, gently draw your belly button toward your spine without flattening your lower back. This is called 360-degree breathing. It teaches the deep core to engage under load properly, before any load is added.

Phase 2: Functional loaded movement (weeks 6-12+) Once you can maintain gentle core engagement during movement without doming, you can introduce very gentle, supported exercises: glute bridges, modified bird dogs, sidelying leg lifts, and seated tall postures against a wall. The emphasis is on maintaining the connection between breath, deep core, and movement.

Phase 3: Progressive loading (months 3-6+) When you can do Phase 2 exercises cleanly without doming and with good control, you can begin adding load: goblet squats, modified push-ups, single-leg standing balance, and gentle dead bugs. The goal is to progressively challenge the core's ability to maintain tension under increasing demand.

Phase 4: Return to full function (months 6-12+) Most women with mild-to-moderate diastasis will see significant improvement through Phases 1-3 and can gradually return to most activities and exercises they want to do. Heavy loading (barbell training, high-impact work) should be introduced progressively and only when midline tension is consistently good.

When to See a Pelvic Floor Physiotherapist

If you have a gap of more than 3 finger-widths at any point, are experiencing back pain, feel a distinct bulge at the midline, or had a C-section — a pelvic floor physiotherapist is strongly recommended. They can do a thorough assessment, give you an individualized program, and monitor your progress.

You don't need a doctor's referral in Australia — you can book directly with a pelvic floor physiotherapist. Many offer telehealth consultations if you're not near a specialist clinic.

The key thing to know: the research consistently shows that supervised, progressive core rehabilitation produces significantly better outcomes than generic advice or trying to fix it alone. There's no replacement for an expert pair of eyes on your specific presentation.

References

1. Sperstad JB, Tennfjord MK, Hilde G, Ellstrom-Engh M, Bo K. (2016). Diastasis recti abdominis during pregnancy and 12 months after childbirth: prevalence, risk factors and report of lumbopelvic pain. British Journal of Sports Medicine, 50(17), 1092-1096.
2. Fernandes da Mota PG, Pascoal AGBA, Carita AIAD, Bo K. (2015). Prevalence and risk factors of diastasis recti abdominis from late pregnancy to 6 months postpartum, and relationship with lumbo-pelvic pain. Manual Therapy, 20(1), 200-205.