Deep Disease
What is catamenial pneumothorax?
The short answer
Catamenial pneumothorax is a collapsed lung that recurs around your menstrual period, most often just before or during bleeding. It is considered part of thoracic endometriosis syndrome and may cause sudden one-sided chest pain or shortness of breath.
Catamenial pneumothorax is a collapsed lung that happens in a repeating pattern around your menstrual period, most often just before or during bleeding. It’s considered part of thoracic endometriosis syndrome, in which endometriosis affects the diaphragm, chest cavity, or (more rarely) lung tissue.
You may notice sudden one-sided chest pain, shortness of breath, or a recurring pneumothorax that seems to return month after month. Routine imaging can confirm the lung collapse but not always reveal its cause, so the timing around your period is an important clue. If your chest symptoms track your cycle, especially with a history of suspected or known endometriosis, our team can help connect the dots and discuss next steps for evaluation and treatment options.
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Worried About Lung Pain During Periods?
Catamenial pneumothorax causes lung collapse around your menstrual cycle and needs expert care. Our specialists diagnose and treat this rare thoracic endometriosis condition to help you breathe easier.
Questions people ask next
All deep disease questionsWhen are thoracic symptoms an emergency?
Sudden, severe chest pain, new or worsening shortness of breath, or faintness should be treated as an emergency, especially around your period. These symptoms can rarely reflect a lung complication linked to endometriosis and need immediate evaluation.
How is thoracic endometriosis treated?
Thoracic endometriosis is usually treated with hormonal suppression, surgery, or both, depending on symptoms, imaging findings, and recurrent chest events. Hormonal therapy aims to reduce cyclic disease activity, while surgery focuses on removing endometriosis and repairing affected areas.
Can a chest CT miss thoracic endometriosis?
Yes, a chest CT can miss thoracic endometriosis because many implants are small, superficial, or blend in with normal tissue. Normal imaging doesn’t rule it out when chest or shoulder pain, shortness of breath, or other symptoms predictably flare around menstruation.
Is thoracic endometriosis dangerous?
Thoracic endometriosis can be dangerous in certain situations, especially when it leads to recurrent lung collapse or significant shortness of breath. With thorough evaluation and coordinated treatment, many patients achieve strong symptom control and fewer recurrences.
Further reading
Thoracic Endometriosis: Understanding Symptoms, Diagnosis, and Treatment Options
Chest pain or shortness of breath during your period? Thoracic Endometriosis Syndrome is a rare but serious condition often missed for years. Learn the signs.
When Endometriosis Affects Your Lungs, What Can Help?
Discover the rare thoracic endometriosis syndrome (TES), its symptoms, and effective treatment options for lung-related endometriosis.
Diaphragmatic Endometriosis: Symptoms and Treatment Options
Learn what diaphragmatic endometriosis is, how it affects the diaphragm, key symptoms, causes, diagnosis options, treatments, and potential complications.
