Endometriosis and Bladder Pain - Why Your Pelvic Pain Persists

When treatment “should” help—but you still hurt

If you’ve been diagnosed with endometriosis (or suspected to have it) and you’ve done the “right” things—hormonal suppression, surgery, pelvic floor therapy, anti-inflammatories—yet your pelvic pain keeps coming back, it can feel defeating and confusing. Many people start to wonder: Is this all in my head? Did my surgery fail? Is my endometriosis “back” already?

One very real possibility is that more than one pain condition is happening at the same time. Chronic pelvic pain is often multi-factorial, meaning your pain system can have multiple drivers—gynecologic, bladder, bowel, musculoskeletal, and nervous system sensitization. That’s not a moral failing or “stress.” It’s biology and lived reality because it is important to remember that while endometriosis can cause a lot of symptoms, it can't cause ALL symptoms in most cases.

Recent evidence pulls one overlap into the spotlight: endometriosis and interstitial cystitis/bladder pain syndrome (IC/BPS) can co-exist more often than many patients are ever told. If your symptoms include urinary urgency, frequency, or bladder pain—especially if endometriosis treatment hasn’t helped—this is worth bringing to your clinician now.

Chronic pelvic pain can have multiple causes (even with confirmed endometriosis)

Chronic pelvic pain is commonly defined as pelvic pain lasting 6 months or longer, sometimes worsening with periods, sex, bowel movements, or bladder filling. It’s also common—affecting an estimated 6–25% of women worldwide—and it can drain your energy, relationships, work, and mental health.

The frustrating part is that chronic pelvic pain can be hard to “solve” with one diagnosis. Even after years of follow-up, a substantial portion of patients still don’t receive a single clear explanation that accounts for everything. That’s why a plan that only focuses on one organ system can leave you stuck: you may treat one pain contributor while another remains active.

Endometriosis is a major driver—but symptoms don’t always match disease “severity”

Endometriosis can absolutely cause chronic pelvic pain (some estimates suggest it contributes in a large share of cases), and it can cause painful periods, pain with sex, bowel pain, fatigue, and more. But one key reality is this: how you feel doesn’t reliably match how extensive endometriosis looks. Someone can have severe pain with “minimal” visible disease, and someone else can have extensive disease with less pain. This may be related to neuronal upregulation or downregulation, peripheral sensitization or central nervous system sensitization.

It’s also common for endometriosis symptoms to overlap with urinary symptoms like burning, frequency, or urgency. That overlap can lead to a dangerous assumption: “It’s just my endometriosis.” Sometimes it is. But sometimes it isn’t the whole story.

This matters because if the bladder is also a pain generator, repeating surgeries or escalating endometriosis-directed treatment may not give you the relief you deserve.

What is IC/BPS (bladder pain syndrome) in plain language?

Interstitial cystitis/bladder pain syndrome (IC/BPS) is typically described as:

• • Pain, pressure, or discomfort that feels related to the bladder, often worse as the bladder fills and sometimes relieved by urinating
  • Lower urinary tract symptoms such as urgency and frequency
  • Symptoms lasting more than 6 weeks, without another clear cause (like a UTI)

IC/BPS is primarily a clinical diagnosis, meaning it’s based on your symptom pattern and on ruling out other conditions. Some people may have a cystoscopy (a camera exam of the bladder), especially if symptoms are severe, don’t respond to initial treatment, or if a clinician is looking for specific findings such as Hunner lesions. But many patients can start an evaluation and initial management without invasive procedures.

If you’ve ever been told “your urine culture is negative, so you’re fine,” you already know how dismissive this can feel. IC/BPS is one reason negative cultures don’t automatically equal “no problem.”

How common is the overlap with endometriosis?

Here’s the patient-relevant bottom line: coexistence appears common in some chronic pelvic pain populations, but the exact rate is uncertain.

Across studies of women with chronic pelvic pain, reported coexistence of endometriosis + IC/BPS ranged from about 15.5% to 78.3%. That is a huge range, and it’s not your job to make it make sense. The big takeaway is simply that it’s not rare for both to be present, and it’s reasonable to screen for bladder pain syndrome when symptoms fit—especially if endometriosis-focused treatment hasn’t worked.

A separate population-based dataset found IC/BPS diagnoses were still uncommon overall (0.20% in people with endometriosis vs 0.05% without over three years), but the relative risk was higher (adjusted hazard ratio 3.74). Translation: depending on the setting and how IC/BPS is diagnosed, the absolute numbers can look small, but the association still signals that clinicians should not ignore bladder symptoms in endometriosis patients.

Signs your bladder may be part of your pelvic pain picture

You don’t need to self-diagnose IC/BPS, but you can notice patterns that help your clinician take you seriously. Bladder involvement is more likely when you recognize symptoms like:

• • Pain that gets worse with bladder filling and eases after peeing
  • Urgency or frequency that doesn’t match infection testing
  • Pain flares triggered by certain drinks/foods (often acidic, caffeinated, carbonated, alcohol—though triggers vary)
  • Pelvic pain that remains even after endometriosis surgery or suppression
  • Pain with sex that feels “deep” and may be paired with urinary symptoms

You can have bladder pain syndrome without all of these. And you can have urinary symptoms from other causes too—which is why proper evaluation matters.

What to do if endometriosis treatment hasn’t helped

If you’ve had little or no improvement after a reasonable trial of endometriosis treatment (medical and/or surgical), it’s appropriate to shift the question from “What’s the next endometriosis treatment?” to:

“What else is contributing to my chronic pelvic pain—and how do we test and treat those contributors?”

This isn’t about doubting your endometriosis diagnosis. It’s about not letting that diagnosis overshadow everything else. Again, endo and adeno most likely cannot cause ALL of your symptoms. Many people with persistent pain benefit from a broader plan that can include bladder-focused evaluation, pelvic floor assessment, bowel evaluation when relevant, and pain-sensitization strategies. Depending on your symptoms, this might involve collaboration between gynecology, urology/urogynecology, pelvic floor physical therapy, and pain-informed care.

Practical takeaways you can use at your next appointment

Bring a short symptom diary (even 1–2 weeks helps): urination frequency, urgency episodes, pain level before/after urinating, period timing, sex-related pain, and any food/drink triggers.

Questions to ask your clinician (choose what fits your situation):

• • If my endometriosis treatment hasn’t relieved my pelvic pain, could IC/BPS or another bladder condition be contributing?
  • What is your process to rule out other causes (UTI, STI, stones, overactive bladder, pelvic floor dysfunction, etc.) before diagnosing IC/BPS?
  • Given my symptoms, would you recommend a urology/urogynecology referral or initial bladder-focused treatment first?
  • If cystoscopy is suggested, what specific question are we trying to answer (for example, Hunner lesions), and how would it change my treatment plan?

Red flags that deserve prompt medical attention include visible blood in urine, fevers/chills, severe flank pain, new urinary retention, or unexplained weight loss—these aren’t typical IC/BPS features and warrant urgent evaluation.

Reality check: why the numbers vary—and why that doesn’t invalidate your symptoms

That wide coexistence range (15.5% to 78.3%) doesn’t mean “almost everyone with endometriosis has IC/BPS.” It means estimates vary a lot depending on who was studied (general population vs specialty clinics), how IC/BPS was defined, and how aggressively people were evaluated.

Also, overlap doesn’t prove one condition causes the other. What it does prove is something much more useful for your daily life: if one treatment path isn’t helping, it’s reasonable—and evidence-supported—to look for additional pain drivers rather than repeating the same steps.

You deserve a plan that matches your full symptom pattern, not just the first diagnosis that landed in your chart.