Can thoracic endometriosis cause a collapsed lung?

Yes. In rare cases, endometriosis can involve the diaphragm or even the chest cavity and lungs, and it can be associated with a spontaneous collapsed lung (pneumothorax) that tends to recur around menstruation—often called catamenial pneumothorax. People may notice one-sided chest pain (commonly right-sided), shortness of breath, or shoulder/chest discomfort that predictably flares just before or during a period.

A key challenge is that imaging like chest X-ray or CT can confirm a lung collapse but often doesn’t identify endometriosis as the cause. When the pattern is cyclical or recurrent, diagnosis may require a coordinated surgical evaluation—sometimes combining minimally invasive pelvic surgery with video-assisted thoracoscopic surgery (VATS)—to look for and treat disease on the diaphragm and in the chest. If this sounds like your experience, our team can help you connect the timing of symptoms to your cycle, evaluate for diaphragmatic/thoracic involvement, and map out next steps for treatment and long-term prevention of recurrence.