Hugh Taylor, MD, on the role and limits of imaging in endometriosis diagnosis

Imaging plays a useful but bounded role in evaluating endometriosis, best suited to ruling out other causes of pelvic pain and identifying severe disease rather than confirming or excluding the diagnosis, according to Hugh Taylor, MD, chair, Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of Medicine. The discussion continues Taylor's remarks on endometriosis as a systemic disease, in a previous interview with Contemporary OB/GYN.²

“One of the most important things we do is use ultrasound to rule out other etiologies of pelvic pain. Fibroids, sometimes adenomyosis, can be seen, and a tumor could be seen,” he said, noting that although endometriosis typically presents with classic progressive, cyclic pelvic pain, other causes are sometimes present.

What imaging can reveal

Taylor noted that imaging can identify certain forms of endometriosis, even as it misses others.

“Sometimes you'll find an endometrioma on ultrasound. Sometimes you will find a nodule of deep infiltrating endometriosis, which is now more commonly recognized by radiologists,” he said.

He emphasized, however, that a negative scan cannot exclude the disease, because its most common form is not visible on imaging.

“You can never rule out endometriosis with an ultrasound or any imaging technique. Superficial peritoneal endometriosis is just a thin film over the surfaces of the peritoneum or other pelvic organs and is typically not seen by ultrasound or by any other imaging, including MRI,” Taylor said. “The most common form of endometriosis we will not see, and you can never say someone doesn't have endometriosis because you don't see it on imaging.”

When to use MRI

Taylor described ultrasound as the preferred first modality, with MRI reserved for select circumstances.

“I will use an MRI if the situation is somehow confusing or maybe for surgical planning in someone who I think has very severe endometriosis. But typically, MRI has a limited role,” he said, reiterating that ultrasound may help rule out other disease but that no imaging technique can reliably diagnose endometriosis.

Taylor's comments align with ACOG's Clinical Practice Guideline No. 11, published February 2026, which for the first time recommends establishing a presumptive diagnosis through symptom-based assessment, physical examination, or both, rather than relying solely on surgical or imaging findings. The shift aims to shorten diagnostic delays that have averaged 4 to 11 years from symptom onset. Endometriosis affects an estimated 10% of women of reproductive age.¹

Reference:

1. Committee on Clinical Practice Guidelines–Gynecology. Diagnosis of endometriosis: ACOG clinical practice guideline no. 11. Obstet Gynecol. Published online February 19, 2026. Accessed September 16, 2026. doi:10.1097/AOG.0000000000006181
2. Fitch J. Endometriosis as a systemic disease, with Hugh Taylor, MD. Contemporary OB/GYN. Published September 14, 2026. Accessed September 18, 2026. https://www.contemporaryobgyn.net/view/endometriosis-as-systemic-disease-hugh-taylor-md