Diastasis recti (divarication of the recti)
Diastasis recti is a widening of the gap between the two rectus abdominis muscles, caused by stretching and thinning of the fibrous tissue that joins them. It is very common after pregnancy and in people who have gained substantial weight, and it is important to be clear about one thing at the outset: it is not a hernia. The abdominal wall is stretched but intact — there is no hole and nothing can become trapped. This distinction determines everything about how it is assessed and treated, and it is the point most often muddled.
How it develops
The two rectus muscles are held together in the midline by the linea alba, a band of interlacing fibrous tissue formed where the aponeuroses of the flat abdominal muscles meet. Its structure allows it to transmit force between the two sides of the abdominal wall.
When the abdomen is distended over a sustained period, the linea alba is subjected to continuous transverse tension. Collagen fibres realign and the tissue stretches and thins — a process called creep. The rectus muscles are displaced laterally, the midline becomes a thin, wide sheet, and the abdominal wall loses its ability to act as a single unit.
The causes reflect the mechanism:
- Pregnancy — much the commonest. The gravid uterus stretches the midline, and hormonal changes (relaxin, progesterone) soften connective tissue. Most cases resolve substantially in the first year after delivery; a proportion do not. Multiple pregnancies, large babies, twins and short inter-pregnancy intervals all increase the likelihood of persistence.
- Obesity and rapid weight change — central fat distends the abdomen from within.
- chronic cough, ascites, and repeated heavy lifting or poorly performed abdominal exercise that generates high intra-abdominal pressure with an unsupported midline
- age, and inherent connective tissue weakness
- in newborns, a physiological and self-resolving finding
Why it causes symptoms
The abdominal wall is not merely a covering. It functions as a container that generates intra-abdominal pressure, stabilises the spine and pelvis, supports posture and assists breathing, coughing and defecation. A stretched midline means the two halves of the wall cannot transmit force to one another, so the transversus abdominis and obliques lose their anchor and become mechanically inefficient. This is why the symptoms are functional — back pain, poor core control, pelvic floor problems — rather than the localised pain of a hernia.
Diastasis frequently coexists with a true hernia — umbilical or epigastric — and this is the clinically important combination. A stretched, thin midline is where small defects appear. Repairing such a hernia while leaving the surrounding weak midline unaddressed is a recognised cause of recurrence.
Symptoms
- a visible midline bulge or ridge, most obvious when sitting up from lying or straining — often described as "coning" or "doming"
- a persistently rounded or protruding lower abdomen despite weight loss and exercise
- low back pain and poor trunk stability
- a feeling of weakness or of the abdomen being unsupported
- pelvic floor symptoms — stress incontinence, pelvic girdle pain, and prolapse symptoms, all of which commonly coexist
- difficulty with lifting, and with returning to exercise after childbirth
- significant distress about appearance, which is a legitimate concern and not a trivial one
Notably, it does not cause the sharp, well-localised, fingertip pain characteristic of an epigastric hernia, and it cannot cause obstruction. Pain of that kind in someone with a known diastasis should prompt a search for a coexisting hernia.
How the diagnosis is made
Examination with the patient lying, then raising the head and shoulders, which tenses the recti and makes the gap palpable. The width is measured at, above and below the umbilicus. A gap of more than about 2cm is generally regarded as abnormal, though function matters more than the number.
Ultrasound measures the inter-rectus distance reliably and, importantly, distinguishes a simple diastasis from a true fascial defect. CT is used where surgery is being planned, to define the width and length of the diastasis, the quality of the tissues, and any coexisting hernia.
The key diagnostic question in practice: is this a diastasis alone, a hernia alone, or both? The answer changes the treatment entirely.
Treatment
Conservative management — the first line, and effective
Most cases, particularly postnatal, improve substantially without surgery, and structured physiotherapy is the treatment of choice.
- Specialist physiotherapy — targeted training of the transversus abdominis and pelvic floor, with progressive loading, breathing coordination and posture work. Assessment by a physiotherapist with expertise in the postnatal abdominal wall and pelvic floor is considerably more useful than generic core exercises.
- Avoiding exercises that increase intra-abdominal pressure against an unsupported midline in the early stages — traditional sit-ups, crunches, double leg raises and unmodified planks — and progressing to them later under guidance.
- Weight management, which reduces the distending force.
- Support garments for symptom relief, alongside rather than instead of strengthening.
- Time — recovery continues for at least a year after delivery, and surgery should not be contemplated before then, nor before a planned further pregnancy.
Surgery
Considered where a significant diastasis persists beyond a year after childbearing is complete, causes functional symptoms or considerable distress, or coexists with a hernia requiring repair.
The operation is plication — the stretched linea alba is folded and sutured to bring the rectus muscles back together, restoring the midline. Mesh reinforcement is added where the tissue is very attenuated, where a hernia coexists, or where the diastasis is wide.
- Open plication, often combined with abdominoplasty where there is significant excess skin, which is frequently the case after pregnancy or major weight loss.
- Laparoscopic or robotic repair — endoscopic and robotic techniques (including eTEP and robotic retromuscular plication) allow plication and mesh placement with small incisions, though they do not address excess skin.
A note on funding and framing: repair is sometimes classed as cosmetic. Where there are genuine functional symptoms, or a coexisting hernia, that classification is questionable, and documenting the functional impairment matters.
Recovery
After plication, hospital stay is typically one to two nights. A support garment is worn for four to six weeks. Return to desk work takes two to three weeks and to full exercise six to eight. Early tightness on standing straight is expected and eases.
Postoperative physiotherapy is essential, not optional — the repair restores the anatomy, but the muscles must be retrained to use it. Seroma is common after abdominoplasty; numbness over the lower abdomen is usual and improves over months.
Recurrence is possible, particularly with further pregnancy or weight gain, which is why surgery is deferred until childbearing is complete.
When to seek an opinion
A persistent midline bulge more than a year after delivery, with back pain, weakness or pelvic floor symptoms. Also, any sharp, localised midline pain or a firm irreducible lump, since that suggests a true hernia rather than a diastasis and is assessed differently.
Common questions
Is this a hernia?
No. The muscles have moved apart and the tissue between them has stretched and thinned, but there is no hole and nothing can become trapped. That is the essential difference: a hernia is a defect with a rim, a diastasis is a stretched but continuous sheet. The two can, however, occur together.
Is it dangerous?
Not in the sense that a hernia can be. There is no risk of bowel becoming trapped. The problems it causes are functional — back pain, weakness, pelvic floor symptoms — and cosmetic, which for many people matters a great deal.
Will it close on its own after pregnancy?
Often, yes, at least substantially, and improvement continues for around a year after delivery. This is why surgery is not considered before then. Structured physiotherapy during that period makes a real difference.
Which exercises should I avoid?
In the early stages, movements that push the abdomen forward against an unsupported midline — traditional sit-ups, crunches, double leg raises and unmodified planks. If you see your midline cone or dome upward during an exercise, that is the sign to modify it. A physiotherapist experienced in postnatal recovery will progress you back to these safely.
Will sit-ups fix it?
No, and done too early they can make the bulge more pronounced. What helps is training the deep abdominal muscle and the pelvic floor to work together, with gradual progression, rather than repeated forceful flexion of the trunk.
Do I need surgery?
Most people do not. Surgery is considered where a significant gap persists more than a year after you have finished having children, where it causes genuine functional problems or distress, or where there is also a hernia that needs repairing. Physiotherapy comes first in nearly every case.
Should I have it repaired at the same time as my hernia?
Usually yes, if the gap is significant. Repairing a small hernia in the middle of a stretched, weak midline leaves the underlying problem in place and makes recurrence more likely. Addressing both together gives a more durable result.
Should I wait until I have finished having children?
Yes. A further pregnancy is likely to stretch the repair again. Where a hernia needs repairing urgently that is a separate matter, but elective plication is best deferred until your family is complete.
Related conditions
Other conditions of the hernias & abdominal wall covered on this site:
- Inguinal hernia (groin hernia)
- Femoral hernia
- Umbilical and paraumbilical hernia
- Epigastric hernia
- Incisional hernia
- Parastomal hernia
- Incarcerated and strangulated hernia
- Rare hernias — Spigelian, lumbar, obturator and others
This page provides general information and does not replace an individual medical consultation. Assessment and treatment are decided for each patient after review of their history and examination.