Pelvic Adhesions
Pelvic adhesions are bands of internal scar tissue that form between organs and tissues that should normally slide freely against one another. They develop after surgery, infection, endometriosis, or any process that inflames the lining of the abdominal cavity, and they represent the body’s healing response rather than a disease in itself. Most cause no problems at all. A minority tether organs in ways that produce chronic pelvic pain, affect fertility by distorting the fallopian tubes, or obstruct the bowel. They present a particular difficulty: they are largely invisible on scans, so diagnosis is usually inferred from history or confirmed only at surgery—and surgery to divide them can itself generate new adhesions.
What is it?
The organs within the abdomen and pelvis are covered by the peritoneum, a thin, smooth, slippery membrane that also lines the cavity walls. A small volume of fluid between these surfaces allows the bowel, uterus, ovaries, and bladder to glide past one another as the body moves, as the bowel contracts, and as organs fill and empty.
Adhesions form when this surface is injured. Surgery, infection, inflammation, bleeding, or irritation damages the peritoneum, and the body responds by laying down fibrin—the same protein scaffold involved in blood clotting—to seal the injury. Normally this temporary scaffold is dissolved by the body’s own enzymes within a few days and the surface heals smoothly. Where that dissolving process is overwhelmed or impaired, the fibrin persists, blood vessels and fibroblasts grow into it, and it matures into permanent fibrous tissue connecting surfaces that should be separate.
Adhesions vary enormously. Some are thin, filmy, and avascular, easily separated. Others are thick, dense, vascular bands that bind organs firmly together. Some are short, tethering two adjacent structures; others are long bands that stretch across the cavity and can loop around bowel.
The consequences follow from the loss of normal movement. Organs that are tethered cannot slide, so movement that would normally be effortless creates traction on the adhesion and on the structures it connects. This traction, and the nerve fibres that grow into mature adhesions, account for the pain some women experience.
The causes are well established.
Surgery is by far the most common. Any abdominal or pelvic operation can produce adhesions, and the risk relates to the extent of tissue handling, the duration of surgery, bleeding, infection, and exposure of the peritoneum to drying, foreign material, and glove powder in the past. Caesarean section, hysterectomy, ovarian surgery, appendicectomy, and bowel surgery are all common precipitants. Laparoscopic surgery produces considerably fewer adhesions than open surgery, which is one of its significant advantages, though it does not eliminate them.
Pelvic inflammatory disease is the second major cause. Infection ascending into the tubes and pelvis produces inflammation that heals with scarring, and this is the mechanism behind the tubal damage and infertility associated with chlamydia and gonorrhoea. Appendicitis, diverticulitis, and any intra-abdominal infection do the same.
Endometriosis causes adhesions through the chronic inflammation that deposits of endometrial-type tissue generate. In severe disease, adhesions can obliterate the space behind the uterus entirely, binding the uterus, ovaries, and bowel into a fixed mass.
Previous bleeding into the abdomen, radiotherapy, inflammatory bowel disease, and retained foreign material all contribute. A proportion of women have adhesions with no identifiable cause.
The crucial point about symptoms is that most adhesions cause none. Adhesions are found incidentally in the majority of women who have had previous surgery, including many who have no pain and no fertility problems. Their presence is therefore not evidence that they are responsible for any given symptom, and this is one of the more difficult aspects of this condition to communicate.
Where symptoms do occur, they fall into three groups.
Chronic pelvic pain is the most common. It is often described as pulling, dragging, or sharp, and characteristically worsens with movement, stretching, exercise, sudden position changes, or when the bladder or bowel is full and distends against a tethered structure. It may be felt in a specific spot, sometimes related to a scar. Unlike endometriosis pain, it does not necessarily vary with the menstrual cycle. Pain that began months after an operation, rather than persisting from the operation itself, fits the pattern of adhesion formation, which takes weeks to months.
Infertility results where adhesions distort the fallopian tubes, block their open ends, or encase the ovaries so that an egg cannot be captured. The tube may be entirely open internally yet unable to function because it is bound down and cannot move freely to collect the egg at ovulation. Adhesions following pelvic inflammatory disease are a leading cause of tubal factor infertility.
Bowel obstruction is the most serious complication. An adhesive band can kink, compress, or form a loop around a segment of bowel, blocking the passage of contents. This produces crampy abdominal pain, vomiting, distension, and inability to pass gas or stool, and requires urgent assessment. Adhesions are the leading cause of small bowel obstruction in adults, and this can occur years or decades after the original surgery.
Deep pain during intercourse is common where adhesions tether the uterus or ovaries, particularly behind the uterus.
The diagnostic problem is substantial and deserves plain explanation, because it accounts for much of the frustration women experience with this condition.
Adhesions are essentially invisible on standard imaging. Ultrasound, CT, and conventional MRI do not show them directly. A normal scan therefore tells you nothing about whether adhesions are present—it neither confirms nor excludes them. Women are frequently told that their scans are normal and interpret this as meaning nothing is wrong, when in fact the test used is simply incapable of answering the question.
The diagnosis is usually inferred rather than demonstrated. A history of surgery, pelvic infection, or endometriosis, combined with a pain pattern that fits, supports it. Examination may reveal a uterus that is fixed rather than mobile, or localised tenderness.
Some techniques do better. Dynamic ultrasound assessment, in which the sonographer applies gentle pressure or asks the woman to breathe deeply while watching whether organs slide against one another, can demonstrate restricted movement suggesting adhesions, and is sometimes called the sliding organ sign. Cine MRI, which captures movement over time rather than a single image, has been used similarly in specialist settings. Neither is widely available, and both depend considerably on operator experience.
Hysterosalpingography and saline sonography assess whether the fallopian tubes are open and are used in fertility investigation, though they show the inside of the tube rather than adhesions outside it.
CT is used when bowel obstruction is suspected, where it identifies the obstruction, its level, and signs of compromised blood supply, though it typically shows the consequence of an adhesion rather than the band itself.
Laparoscopy remains the only definitive means of diagnosis, allowing adhesions to be seen directly and divided at the same time. Its limitation is that it is surgery, with its own risks and its own potential to generate new adhesions, so it is not undertaken simply to confirm a suspicion.
Important to Know
Pelvic adhesions present an unusual situation in which the treatment can cause the problem it is intended to solve. This paradox shapes every management decision and is worth understanding before considering surgery. Care is typically coordinated by gynaecologists, with pain specialists, physiotherapists, fertility services, and surgical teams involved as relevant.
Most adhesions require no treatment. Their presence alone is not a reason to operate, and a woman told she has adhesions found incidentally during an operation does not need anything done about them.
Where surgery is being considered for pain, the evidence deserves honest presentation. Adhesiolysis—dividing adhesions laparoscopically—relieves pain in some women, but randomised trials comparing it with diagnostic laparoscopy alone have largely failed to show a convincing benefit, and adhesions reform in a substantial proportion afterwards. This does not mean surgery never helps; women with dense adhesions causing a clear mechanical problem may improve considerably. But it does mean that repeated operations for pain, each generating new scar tissue, is a pattern that often leaves a woman worse rather than better. A second or third adhesiolysis for ongoing pain warrants careful thought and ideally a second opinion.
For infertility, the case is clearer. Where adhesions distort the tubes or encase the ovaries, laparoscopic division can restore anatomy and improve the chance of natural conception. Where tubal damage is extensive, in vitro fertilisation bypasses the problem entirely and is often the more effective route, since it does not depend on the tube functioning at all. The choice depends on the extent of damage, the woman’s age, and other fertility factors, and this is a decision worth making with a reproductive specialist rather than a general surgical team.
Bowel obstruction is managed urgently. Many episodes settle with conservative treatment—nothing by mouth, intravenous fluids, and a tube to decompress the stomach—allowing the bowel to recover without surgery. Where there are signs that the bowel’s blood supply is compromised, or where obstruction does not resolve, surgery is required. Anyone with a history of abdominal surgery who develops crampy pain with vomiting and inability to pass gas or stool should seek urgent assessment rather than waiting.
Pain management approaches are often more valuable than further surgery and are frequently underused. Chronic pelvic pain involves changes in how the nervous system processes pain signals, which persist regardless of whether the original mechanical cause is addressed. Specialist pelvic pain services, physiotherapy including manual techniques and pelvic floor work, neuropathic pain medications, and psychological approaches to pain management all have a role. These are not an admission that the pain is imaginary—they address the real physiology of persistent pain.
Prevention is the area where most progress has been made, and it matters for any woman facing surgery. Laparoscopic approaches generate substantially fewer adhesions than open surgery and should be used where appropriate. Careful surgical technique—gentle tissue handling, meticulous control of bleeding, avoiding unnecessary drying of tissues, minimising foreign material, and limiting operating time—reduces formation. Adhesion barrier products, placed at the end of surgery as films or gels to keep surfaces separated during healing, reduce adhesion formation in trials, though whether they translate into fewer symptoms or fewer obstructions remains less well established. Asking a surgeon about their approach to adhesion prevention is reasonable, particularly for women who have had previous adhesion problems.
A word about expectations is appropriate. Adhesions are common, often asymptomatic, and when symptomatic are difficult to treat definitively. Women with adhesion-related pain frequently encounter a frustrating sequence: normal scans, uncertainty about whether adhesions are the cause, surgery that helps temporarily, and recurrence. This is a genuinely difficult condition rather than a failure of care, and understanding why it is difficult often helps more than another intervention.
Adhesions and endometriosis frequently coexist, and distinguishing which is causing pain can be impossible. Treating one without addressing the other may produce only partial improvement, and this is a common reason for disappointing results after surgery.
Care is coordinated by gynaecology, with pelvic pain services, physiotherapy, fertility medicine, and colorectal surgery as needed. Imaging has limited value for the adhesions themselves, so clinical history carries unusual weight in this condition.
Patient education plays an important role. Understanding that adhesions are common and usually harmless, that a normal scan cannot exclude them, that surgery to divide them can create new ones, that evidence for surgery relieving pain is limited, that IVF often bypasses adhesion-related infertility more effectively than surgery, and that bowel obstruction symptoms require urgent attention all contribute to appropriate care and more realistic expectations.
Red flag symptoms include crampy abdominal pain with vomiting, abdominal distension, and inability to pass gas or stool, which suggests bowel obstruction and requires immediate emergency assessment; severe or rapidly worsening abdominal pain; a rigid, exquisitely tender abdomen; fever with abdominal pain; persistent vomiting with inability to keep down fluids; and any of these in a woman with previous abdominal or pelvic surgery, in whom adhesive obstruction is the leading explanation. Sudden severe pelvic pain may indicate ovarian torsion or another acute cause and also warrants urgent assessment.