I have been doing a little bit of extra research into endo, pelvic pain and central sensitivity and came across this paper that dives into pelvic tenderness and pain sensitivity in women with endometriosis and chronic pelvic pain (CPP). I wanted to spotlight it because it’s one of those studies that puts evidence behind what so many of us see in clinic, clients who don’t just have “pelvic pain,” but have pain that feels amplified, unpredictable, and far-reaching.
Let’s unpack it.
Shafrir AL, Martel E, Missmer SA, et al. (2021). Pelvic floor, abdominal and uterine tenderness in relation to pressure pain sensitivity among women with endometriosis and chronic pelvic pain.
European Journal of Obstetrics & Gynecology and Reproductive Biology, 264:247–253.
The researchers wanted to know whether tenderness in the pelvic floor, abdomen, and uterus was linked with central nervous system pain amplification. To measure this, they used a pressure pain threshold test on the non-dominant thumbnail (yes you read that right… the thumbnail!) a really cool way to see if someone has lower pain thresholds outside of the pelvic region.
What they did:
Participants: 88 women aged 18–50 with endometriosis and/or CPP.
Tenderness testing: 6 abdominal sites, 6 pelvic floor sites, and 1 uterine site. Pressure was applied and women rated pain on a 0–10 scale. Pain ≥4/10 counted as “high tenderness.”
Central sensitisation measure: Pressure was applied to the non-dominant thumbnail using a validated QST (quantitative sensory testing) protocol.
- Why the thumbnail? Because it’s a non-pelvic site. If someone feels pain at lower-than-expected levels here, it suggests their nervous system is “turned up” globally, a sign of central sensitisation.
Group comparisons within the study:
- Endometriosis without pain
- Endometriosis with pain
- CPP without endometriosis
So what did they find?
Prevalence of tenderness
- 50% had high pelvic floor tenderness
- 42% had high abdominal tenderness
- 58% had high uterine tenderness
Central sensitisation link
- Women with high pelvic floor tenderness had lower pain thresholds on the thumbnail test, meaning they experienced pain at much lower levels of pressure.
- No significant associations were found for abdominal or uterine tenderness.
Group differences
- Women with endometriosis without pain showed far less tenderness compared to women with painful endometriosis or CPP.
Impact on quality of life
- High tenderness in any region was linked to:
- More severe dysmenorrhea (painful periods)
- Higher rates of dyspareunia (painful intercourse)
- Greater pain intensity overall
- Poorer quality of life scores across multiple domains
So, what does this mean for us in practice?
- Pelvic floor tenderness = poor function (or at least that’s how I see it). Tender muscles are rarely functional muscles. In the pelvic floor, tenderness may signal that muscles are stuck in a shortened position with poor eccentric control. This impacts load transfer, coordination, and movement. Think about how this might affect a client who is trying to exercise, especially with lower body movements.
- Indirect screening. As EPs,we don’t perform internal exams, but central sensitivity screening may give us indirect clues about pelvic floor tenderness and poor function for our clients.
- Improve the pelvic floor without even touching it. Exercise programs designed to target central pain mechanisms (graded exposure, variability, relaxation, nervous system down-regulation) may reduce pelvic floor tightness without internal release. Clinically, I see this happen all the time with my clients.
- Be careful with pressure-point therapies. For women with central sensitisation, pressure-based pelvic floor release can actually flare pain rather than relieve it. I have heard reports of this with many of my clients and they have chosen to move away from manual internal release work for this exact reason. Exercise may be a safer and more effective option for these people.
- Whole-body strategies matter. Movement that restores variability, integrates breath, and gradually loads tissues may be the key to restoring coordination and reducing pain amplification.
That’s another Research Spotlight done and dusted. Remember, our job isn’t just to know the research, it’s to apply it in ways that truly change women’s lives.
Have a fabulous day wherever you are and I’ll catch you in the next one… BYE!