Can endometriosis affect the diaphragm or lungs?

Yes. While endometriosis is usually confined to the pelvis, it can also involve the upper abdomen—especially the diaphragm—and, more rarely, extend into the chest cavity or lungs (often grouped under “thoracic endometriosis syndrome”). Diaphragmatic involvement is one of the more common non-pelvic locations, and it tends to be on the right side.

When endometriosis affects the diaphragm or chest, symptoms often follow a menstrual pattern and can include right-sided chest or upper abdominal pain, shoulder or arm pain, and pain with deep breathing or coughing. In rare cases, it may contribute to shortness of breath, recurrent lung collapse around periods (catamenial pneumothorax), fluid or blood around the lung, or coughing up blood.

Diagnosis can be challenging because imaging may not clearly show endometriosis even when symptoms are real and cyclical. In our practice, we take these symptoms seriously and plan evaluation with the “whole picture” in mind—often including careful surgical inspection of the diaphragm during endometriosis surgery, and coordinating with thoracic surgery when there’s concern the disease may be inside the chest. If you’re noticing cyclical chest, shoulder, or breathing symptoms, reach out to our team so we can help you connect the dots and map out next steps.