Could this blood test finally catch missed endometriosis cases?

For decades, endometriosis has been defined as much by diagnostic delay as by disease burden. 

Patients often spend years cycling through imaging, empiric treatments, and referrals, only to land on a diagnosis after laparoscopy. Now, a new generation of blood-based diagnostics may begin to disrupt that paradigm.

A recent study suggests that a novel blood test can identify endometriosis cases that standard imaging misses, raising important counseling considerations for physicians. ^[]

The headline finding: catching what imaging misses

Endometriosis lesions—especially superficial peritoneal disease—are notoriously difficult to visualize on ultrasound or even MRI. A test that identifies over half of these “invisible” cases could meaningfully shorten the diagnostic journey.

“If women, or even girls entering puberty, had access to a test like this, it could alert them to potential endometriosis much sooner in life. That could mean earlier treatment that would save women from years of pain, and it could potentially preserve their ability to get pregnant,” Brittney Bastow, MD, a Colorado-based OB/GYN, told Kaiser Permanente. ^[]

Why this matters: the diagnostic gap is still wide

Despite advances in imaging and awareness, endometriosis diagnosis remains delayed:

• Average time to diagnosis: 4–11 years ^[]

• Gold standard: laparoscopic visualization with histology ^[]

• Imaging sensitivity: variable, operator-dependent ^[]

This gap has real consequences: chronic pain, infertility, repeated surgeries, and psychological burden.

Blood-based biomarkers aim to shift diagnosis earlier and upstream, potentially before irreversible damage occurs.

How to counsel patients right now

Patients will likely encounter headlines framing this as a “simple blood test for endometriosis.” It's not wrong, but it’s incomplete.

1. Emphasize:This is promising, not definitive (yet)

• Blood tests are not yet widely adopted as standalone diagnostics

• Positive results may still require confirmation (often surgical)

• Clinical validation is ongoing across diverse populations

Suggested framing: “This could become a helpful tool to guide diagnosis earlier, but it doesn’t fully replace current methods yet.”

2. Use it as a rule-in or risk-stratification tool

For patients with chronic pelvic pain, infertility, and/or negative imaging but persistent symptoms, a blood test may:

• Support earlier referral to gynecology or endometriosis specialists

• Justify empiric treatment trials

• Reduce dismissal of symptoms when imaging is normal

3. Be careful about false reassurance

With 80% sensitivity, false negatives still occur. If clinical suspicion is high:

• Do not rule out endometriosis based on a negative test alone

• Continue workup or refer as appropriate

4. Prepare patients for access and cost questions

Blood tests for endometriosis are:

• Early commercial or limited-release

• Not universally covered by insurance

• Still being integrated into guidelines

Patients may ask, “Can I get this now?”—and the answer may depend on geography and provider networks.