Is “Round Ligament Pain” Really the Round Ligament?
What emerging research on Pregnancy-Related Abdominal Wall Neuropathy (PRAWN) means for clinicians.
Sharp pain in the lower abdomen during pregnancy? For decades, there has been an almost automatic explanation: “It's probably round ligament pain.”
The traditional explanation is familiar to most clinicians who work with pregnant patients: as the uterus grows, increasing tension or stretching of the round ligaments produces sharp, pulling, or aching pain in the lower abdomen or groin—particularly with movement.
It is so embedded in pregnancy care that “round ligament pain” has become part of the everyday vocabulary surrounding pregnancy.
But there is a problem...
The evidence supporting the round ligament as the actual pain generator is surprisingly limited.
And a growing body of emerging research is asking whether at least some of the pain we've historically attributed to the round ligament may actually have a neuropathic source within the abdominal wall. Enter to the chat: Pregnancy-Related Abdominal Wall Neuropathy—or PRAWN.
Wait...Do We Actually Know That the Round Ligament Hurts?
This is where things get interesting. In a pilot cohort investigating unexplained abdominal pain during pregnancy, Twidale and colleagues noted that although round ligament pain is widely referenced in clinical practice and obstetric literature, their literature search found no studies establishing the etiology or defining diagnostic features of RLP, and very little research examining its treatment.
Yet the diagnosis is used routinely. The researchers surveyed 203 pregnant adults beyond 20 weeks' gestation. Approximately 68.5% reported unexplained abdominal pain, and 54% were familiar with the term “round ligament pain.”
Here's the particularly interesting part: Among participants experiencing unexplained abdominal pain, 98.6% described at least one feature also associated with abdominal wall pain.
Common descriptors included pain that was:
aggravated by walking, bending, or moving to sitting
sharp
consistently located in the same area
That doesn't prove that round ligament pain doesn't exist.
But it raises a very reasonable clinical question: What if we're attributing some pregnancy-related abdominal pain to the wrong structure?
Meet PRAWN
Pregnancy-Related Abdominal Wall Neuropathy (PRAWN) describes abdominal wall pain thought to result from irritation or entrapment of sensory nerves as the abdominal wall changes during pregnancy.
The proposed mechanism makes anatomical sense. The lower thoracic and abdominal cutaneous nerves travel through layers of the abdominal wall to provide cutaneous sensation. Other nerves—including the iliohypogastric and ilioinguinal nerves—also traverse regions undergoing substantial mechanical change as pregnancy progresses.
As the uterus expands and the abdominal wall accommodates increasing volume and tension, these neural pathways may become irritated, stretched, compressed, or mechanically sensitive. In other words, maybe the pain isn't simply coming from a ligament being stretched.
Maybe we're looking at a nerve.
PRAWN has been proposed as an umbrella term encompassing pregnancy-associated abdominal wall nerve entrapment presentations, including anterior, lateral, and posterior cutaneous nerve involvement. Recent published cases describe sharply localized abdominal or back pain, focal tenderness, sensory changes, positive abdominal-wall provocation testing, and improvement following targeted intervention.
The Clinical Presentation Starts to Look Different
If we assume the round ligament is responsible, our examination may stop there. But if abdominal wall neuropathy enters the differential diagnosis, suddenly we have more questions to ask.
Where exactly is the pain?
Can the patient point to it with one finger?
Is it consistently in the same location?
Is there burning, stabbing, electric, sharp, or shooting pain?
Is there hypersensitivity or altered sensation over the abdominal wall?
Does movement reproduce it?
Can palpation reproduce it?
Does abdominal wall contraction change the symptoms?
These questions move us away from simply labeling a symptom based on pregnancy status and toward identifying a potential pain mechanism. And that is much more useful clinically.
Carnett's Sign: A Simple Test Worth Knowing
One examination technique appearing in the PRAWN literature is Carnett's test, historically used to help distinguish abdominal wall pain from visceral abdominal pain.
The clinician first identifies the patient's tender area while the abdominal wall is relaxed. The patient then contracts the abdominal musculature—for example, by lifting the head and shoulders or raising the legs—while the clinician reassesses the painful area.
If tenderness persists or increases with contraction, an abdominal wall source becomes more likely. If the pain decreases as the abdominal wall contracts, a visceral source may be more likely.
Recent PRAWN reports have described positive Carnett's testing alongside focal pain and sensory findings as part of the clinical presentation. Importantly, Carnett's sign does not diagnose PRAWN by itself, nor should abdominal wall testing replace appropriate medical screening of abdominal pain during pregnancy. It is one piece of the clinical picture.
This Is Where Pelvic Health PT Gets Interesting
For pelvic health clinicians, the PRAWN conversation matters because it changes what we ask during an evaluation.
Instead of “How do I treat round ligament pain?”, we can ask: “What tissue or neural structure appears to be contributing to this patient's symptoms?”.
That might lead us to assess:
pain location and distribution
sensory changes
abdominal wall sensitivity
thoracic and lumbar mobility
abdominal wall loading
breathing mechanics
trunk movement
hip and pelvic mechanics
positions or movements that increase neural loading
movement strategies associated with symptom reproduction
And importantly "Does the presentation actually behave like the diagnosis we've given it?".
That's clinical reasoning.
Can Physical Therapy Treat PRAWN?
This is where we need to separate promising clinical observations from established evidence.
A 2025 case report published in the Journal of Pelvic, Obstetric and Gynaecological Physiotherapy described a pregnant patient with abdominal pain, focal hyperesthesia, site-specific symptoms, and a positive Carnett's test. Treatment included patient education, manual therapy, and targeted stretching. The patient's reported pain decreased from 5/10 to 0/10 with complete symptom resolution.
That's interesting. But it's only one case report.
It tells us that rehabilitation may have a role and gives us hypotheses worth investigating. It does not establish a standardized PRAWN treatment protocol. And that's exactly where we should resist the urge to turn an emerging diagnosis into another recipe.
PRAWN treatment isn't a protocol. It's another potential mechanism to consider.
What About Nerve Blocks?
The interventional literature adds another interesting piece. Published PRAWN cases have described substantial or rapid symptom improvement following ultrasound-guided local anesthetic nerve blocks. A recent case involving anterior, lateral, and posterior cutaneous nerve entrapment reported rapid resolution after targeted local anesthetic injections.
Earlier case-series work also described pregnant patients with suspected anterior cutaneous, ilioinguinal, or iliohypogastric nerve entrapment who experienced immediate relief following ultrasound-guided abdominal wall blocks.
A positive response to a targeted anesthetic block strengthens the argument that, in at least some patients, the abdominal wall and its neural structures—not simply the round ligament—may be important pain generators.
Again, this doesn't prove that every patient diagnosed with RLP actually has PRAWN.
But it certainly gives us reason to expand our differential.
The Bigger Clinical Lesson
PRAWN is fascinating. But I think the larger lesson extends beyond pregnancy. In healthcare, diagnostic labels have a way of becoming explanations.
We hear “Round ligament pain.” and eventually we stop asking, “How do we know?”.
Emerging research doesn't mean we discard everything we've previously believed every time a new hypothesis appears. It means we stay curious. We revisit anatomy. We examine the patient in front of us. We distinguish what has been demonstrated from what has simply been repeated long enough to feel established.
And when the clinical presentation doesn't fit the traditional explanation?
We keep asking better questions.
Because perhaps the most important question isn't “How do we treat round ligament pain?”. Maybe it's “Are we sure it's the round ligament?”.
Ready to Take This Into the Clinic?
PRAWN is a perfect example of why pregnancy and postpartum rehabilitation requires more than memorizing a list of “common pregnancy complaints.” As our understanding of these conditions evolves, so should the way we evaluate, educate, and treat the patients in front of us. In our Pregnancy & Postpartum Considerations course, we dig into PRAWN and other pregnancy- and postpartum-specific presentations through the lens of anatomy, neurophysiology, dry needling, safety, and—most importantly—clinical reasoning.
Because the goal isn't simply to learn where to treat. It's to understand what you're treating, why you're treating it, and how that intervention fits into a comprehensive rehabilitation plan.
Ready to think differently about pregnancy and postpartum care? Join us for Pregnancy & Postpartum Considerations.
References
Halpin S, Camano I, Twidale E. Pregnancy-related abdominal wall neuropathy—PRAWN: a common and treatable cause of pain in pregnancy. A case series. Aust N Z J Obstet Gynaecol. 2021;61(suppl 1). doi:10.1111/ajo.13345.
Parr RE. Targeted physiotherapy for pregnancy-related abdominal wall neuropathy. J Pelvic Obstet Gynaecol Physiother.2025;136:69-77. doi:10.62399/NCFK1831.
Kosaka S, Watari T, Ishizuka K. Pregnancy-related abdominal wall neuropathy (PRAWN) presenting with combined anterior, lateral and posterior cutaneous nerve entrapment syndromes. BMJ Case Rep. 2025;18(7):e266571. doi:10.1136/bcr-2025-266571.
Tu FF, Hellman KM, Backonja MM. Gynecological management of neuropathic pain. Am J Obstet Gynecol.2011;205(5):435-443. doi:10.1016/j.ajog.2011.05.011.
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