Catamenial Pneumothorax · Thoracic Endometriosis · VATS Surgery · London
Your lung keeps collapsing around your period. This is not a coincidence.
Catamenial pneumothorax is a specific, diagnosable, and treatable condition — a form of thoracic endometriosis where endometrial tissue causes cyclical lung collapses timed to menstruation. It is consistently missed until someone asks the right question. This page is for women who have finally found the right words for what keeps happening to them.
For women who already know something is wrong — but haven’t yet been believed
You’ve been to A&E three times. Each time: a chest drain, pain, recovery — and then it happens again.
Same side. Same time of month. Something connects these events that nobody has named yet.
The pattern is not subtle, but the medical system tends to process each episode in isolation. A collapsed lung is treated, the drain is removed, you go home. A month later it happens again. Another drain. The word “spontaneous” is used — implying random, unpredictable, unconnected. But you have noticed. It is not random. It is your period.
Catamenial pneumothorax is a recognised medical entity where endometrial tissue — the same tissue that causes endometriosis in the pelvis — migrates into the thoracic cavity. It deposits on the diaphragm, the pleura, and sometimes the lung surface. At menstruation it responds to hormonal cycling, breaks down, bleeds, and creates holes through which air escapes into the pleural space — collapsing the lung.
“Most patients I see with catamenial pneumothorax have already had three or more chest drain insertions before someone connects the timing to their cycle. The diagnosis is not difficult once you ask the question — but in a busy emergency department, the question is almost never asked. The patient has to bring the information.”
This page is for you if you’ve had recurrent pneumothorax timed to your menstrual cycle. It explains what is happening, how it is confirmed, and what treatment involves — both the surgical component (VATS) and the hormonal component (gynaecology), because treating only one is not enough.
Book a Specialist Consultation
Seen within days. No referral needed. Mr Scarci specialises in catamenial pneumothorax and works with a dedicated gynaecology MDT team.
Call 020 8090 5119
Why diagnosis is so often delayed
The journey to diagnosis — what most catamenial pneumothorax patients go through
Studies show an average of three or more pneumothorax episodes before the catamenial pattern is recognised. Here is what that journey typically looks like.
Right-sided chest pain and breathlessness — A&E admission
Sudden sharp chest pain on the right, breathlessness. X-ray shows a right-sided pneumothorax. Chest drain inserted. After 2–3 days you’re discharged, told it was a “spontaneous pneumothorax.” You may be slim and young, which apparently explains it. Nobody asks where you are in your menstrual cycle.
→ Diagnosis: “Primary spontaneous pneumothorax” — underlying cause unaddressed
Same side. Same symptoms. Another chest drain — and this time surgery is discussed.
It happens again. Same right side. You notice it’s around your period again — but it isn’t acted on. VATS bullectomy and pleurodesis may be performed for “recurrent spontaneous pneumothorax.” The histology from the lab may actually say “endometriosis” — but nobody links this to the treatment plan.
→ Surgery for “recurrent PSP” — underlying thoracic endometriosis not addressed
It comes back. Even after a procedure that should have prevented it.
Recurrence after VATS that should have been preventive is the most common trigger for catamenial pneumothorax finally being suspected. An experienced thoracic surgeon asks about menstrual timing. You confirm the pattern. The pieces come together for the first time.
→ Recurrence post-VATS: first strong signal that something specific is being missed
The diagnosis is made — often in the first appointment with the right specialist
A thoracic surgeon familiar with catamenial pneumothorax asks the right questions: timing relative to menstruation, right-sided predominance, history of pelvic endometriosis. Targeted VATS — this time looking specifically for diaphragmatic fenestrations and thoracic endometriosis implants — is planned alongside gynaecological input for post-operative hormonal management.
→ Diagnosis: catamenial pneumothorax — thoracic endometriosis syndrome confirmed
Surgery + hormonal management — the monthly pattern is finally broken
VATS addresses the structural thoracic pathology: endometrial implants excised, diaphragmatic fenestrations repaired, pleurodesis performed. Post-operatively, hormonal suppression eliminates the cyclical hormonal stimulus that drives recurrence. For the first time, your period arrives without a lung collapse.
→ No further pneumothorax — cycle broken with combined surgical and hormonal treatment
How thoracic endometriosis causes catamenial pneumothorax
Endometriosis occurs when endometrial-like tissue grows outside the uterus. The thoracic cavity is the most common site of extra-pelvic endometriosis — deposits form on the diaphragm, the pleural surfaces, and occasionally within the lung parenchyma. This ectopic tissue responds to the same hormonal signals that drive menstruation.
Diaphragmatic fenestrations (holes)
Endometriosis erodes perforations through the diaphragm, allowing air to pass from the abdominal cavity into the pleural space at menstruation. The most important finding the surgeon must look for at VATS.
Pleural implants
Deposits on the visceral pleura weaken the lung surface, creating areas of fragility that rupture at menstruation, releasing air directly into the pleural space.
The result in both cases is identical: a cyclical, predictable, right-sided pneumothorax occurring within 72 hours of menstruation onset — and recurring every month without definitive treatment.
Thoracic endometriosis syndrome — the full clinical spectrum
Catamenial pneumothorax is the most common manifestation of thoracic endometriosis syndrome (TES) — but it exists alongside other presentations that can occur separately or together.
Catamenial Pneumothorax
Recurrent lung collapse within 72 hours of menstruation onset. Almost exclusively right-sided (~90%). The most frequently diagnosed and most surgically treatable form of TES.
Catamenial Haemothorax
Blood in the pleural cavity occurring cyclically with menstruation — endometrial tissue bleeding into the pleural space rather than causing air leaks. May co-exist with pneumothorax.
Catamenial Haemoptysis
Coughing up blood occurring cyclically at menstruation — caused by endometrial tissue within the lung parenchyma that bleeds with each cycle. Should immediately raise suspicion of thoracic endometriosis.
Pulmonary Nodules
Endometrial implants within the lung parenchyma appearing as nodules on CT. May be discovered incidentally during workup for a suspected malignancy. VATS resection is both diagnostic and therapeutic.
Catamenial chest pain and right shoulder tip pain — the overlooked signals. Up to 80% of women with thoracic endometriosis report catamenial chest pain that does not reach the threshold of a full pneumothorax. Right shoulder tip pain around the period — referred from diaphragmatic irritation via the phrenic nerve — is a classic but frequently unrecognised symptom. These symptoms in a woman with known pelvic endometriosis should prompt investigation for thoracic involvement even without a documented collapse.
Could your recurrent pneumothorax be catamenial?
If several of these describe your experience, a specialist consultation is warranted
Regardless of what previous doctors have told you.
Timing within 72 hours of period
Your collapsed lung happened on or just before/after your period started
Right-sided pneumothorax
Your collapses are always or almost always on the right side
Recurrent episodes
You’ve had two or more pneumothorax events
Known pelvic endometriosis
You’ve been diagnosed with endometriosis affecting the pelvis
Right shoulder tip pain with period
Right shoulder pain around your cycle even without a full pneumothorax
Recurrence after previous VATS
Surgery that should have prevented recurrence — and it happened again
Cyclic chest pain without collapse
Right-sided chest pain following a monthly pattern, even without documented collapse
Catamenial haemoptysis
You have coughed up blood at the time of your period
How catamenial pneumothorax is properly diagnosed
The diagnosis is primarily clinical — built from the pattern of symptoms. Imaging plays a supporting role. VATS provides definitive confirmation and simultaneous treatment.
Clinical History
A detailed menstrual history is the single most important diagnostic tool. Recurrent right-sided pneumothorax within 72 hours of menstruation onset in a woman of reproductive age is sufficient clinical basis for diagnosis.
→ The diagnosis is made by asking the question that nobody has asked
VATS — Diagnostic AND Therapeutic
VATS is both the definitive diagnostic tool and the primary treatment. The surgeon directly visualises the thoracic cavity — identifying diaphragmatic fenestrations, pleural implants, and endometrial deposits. Treatment proceeds in the same operation.
→ Confirms thoracic endometriosis in ~52% of cases at surgery
Chest X-Ray and CT
X-ray confirms the pneumothorax. CT may reveal small diaphragmatic defects. However, a normal CT does NOT exclude catamenial pneumothorax — many diaphragmatic fenestrations are invisible on pre-operative imaging.
→ Normal CT does not exclude the diagnosis
MRI of Chest and Pelvis
Pelvic MRI confirms concurrent pelvic endometriosis and guides gynaecological planning. Chest MRI can identify larger pleural-based endometrial deposits. For detecting small diaphragmatic fenestrations, VATS remains essential.
→ Pelvic MRI guides gynaecological treatment planning
Combined VATS + Gynaecological Laparoscopy
For women with significant pelvic endometriosis, combined VATS and laparoscopy may be performed at the same operating session. Concurrent pelvic endometriosis is found in 50–80% of catamenial pneumothorax patients.
→ VATS typically performed first, followed by laparoscopy at the same anaesthetic
Hormonal Response Test
When diagnosis remains uncertain, a trial of hormonal suppression (OCP or GnRH agonist) that eliminates menstrual cycling can serve a diagnostic function. Abolition of episodes during suppression strongly supports the catamenial diagnosis.
→ Confirms diagnosis but does not substitute for VATS
Why catamenial pneumothorax requires a multidisciplinary team
Treating only one dimension reliably leads to recurrence
Surgery alone, without post-operative hormonal suppression, carries a recurrence rate of up to 32%. Hormonal therapy alone does not repair diaphragmatic fenestrations or remove pleural deposits. The evidence consistently shows that surgery plus hormonal management produces significantly lower recurrence than either alone.
Thoracic Surgeon (Mr Marco Scarci)
VATS surgery: diaphragmatic repair, implant resection, pleurodesis, apicectomy. Surgical planning and post-operative thoracic follow-up.
Gynaecologist / Endometriosis Specialist
Pelvic endometriosis assessment, laparoscopy when indicated, post-operative hormonal management prescribing and monitoring.
Histopathologist
Confirms diagnosis of thoracic endometriosis on VATS tissue samples using immunohistochemistry for oestrogen/progesterone receptors.
Respiratory Physician
Pre-operative respiratory assessment and pulmonary function testing. Consulted as needed for ongoing respiratory management.
VATS surgery for catamenial pneumothorax — what the operation involves
The goal is diagnostic, therapeutic, and structural — finding and treating every source of thoracic endometriosis while preventing future pneumothorax through pleurodesis. This is not the same operation as VATS for standard spontaneous pneumothorax.
Unlike standard VATS for spontaneous pneumothorax — which focuses primarily on apical blebs — VATS for catamenial pneumothorax requires a systematic survey of the entire thoracic cavity: the diaphragm, all pleural surfaces, the lung apex, and the visceral pleura. Performed under general anaesthetic, typically 2–3 hours. In most cases the patient goes home within 3–5 days.
Diaphragmatic Repair
Holes in the diaphragm — found in ~87% of thoracic endometriosis cases — are the primary source of catamenial pneumothorax. Depending on size and number, they are repaired by direct suture closure, selective diaphragmatic plication, or partial diaphragmatic resection with mesh reconstruction.
→ Found in 87.5% of cases at VATS in published series
Implant Excision & Biopsy
All visible endometrial deposits on the visceral pleura, parietal pleura, and diaphragm are excised or ablated. Tissue is sent for histological confirmation. Systematic exploration is essential — small deposits are easily missed by a surgeon not specifically looking for them.
→ Diaphragmatic lesions 38.8%; visceral pleura 29.6% in published series
Apicectomy
When dystrophic lung tissue, blebs, or bullae are present at the lung apex — found in ~62% of catamenial pneumothorax cases at VATS — surgical removal is performed. These may contribute to air leaks independently of the endometriosis.
→ Performed in ~62% of cases alongside diaphragmatic repair
Combined Pleurodesis
Both mechanical pleurodesis (abrading pleural surfaces) and chemical pleurodesis (sterile talc powder) are performed in all cases to maximise recurrence prevention. This dual approach provides an additional layer of protection beyond the structural repairs.
→ Combined mechanical + chemical pleurodesis in all cases
Hormonal therapy — why surgery alone is not enough
⚠️ The recurrence problem — why hormonal therapy after surgery is mandatory. Published data show recurrence rates of 20–32% after VATS alone for catamenial pneumothorax — even with excellent surgical technique. The reason: surgery removes existing lesions but cannot prevent new endometrial deposits forming if the hormonal driver (the menstrual cycle) continues. Post-operative hormonal suppression is not optional.
Combined Oral Contraceptive Pill
Continuous (no pill-free breaks) OCP eliminates menstrual cycling and significantly reduces endometrial tissue activity. Well-tolerated, widely available, usually first post-operative choice.
GnRH Agonists (Zoladex, Prostap)
Powerful suppression of ovarian oestrogen creating a temporary menopausal state. Highly effective for severe cases. Used for 6 months post-operatively with bone-protecting HRT add-back.
Progestogens
Progestogen-only therapy suppresses endometrial activity without oestrogen. Various formulations — oral, injected, or via Mirena IUS. Preferred when oestrogen-containing preparations are contraindicated.
Danazol
An androgenic steroid suppressing both oestrogen and progesterone. Effective but associated with androgenic side effects. Less commonly first-line; appropriate for selected cases.
Aromatase Inhibitors
Letrozole and anastrozole target local oestrogen production in endometrial tissue. Used in specialist centres for cases refractory to standard hormonal approaches.
Fertility considerations
Women wishing to conceive need a tailored approach — all hormonal options are contraceptive. Careful planning between thoracic surgeon and gynaecologist is essential to balance recurrence risk with fertility goals.
Important: Hormonal therapy is managed by your gynaecologist in coordination with thoracic follow-up. Never discontinue hormonal therapy without discussing with your treating team first — premature withdrawal is the most common cause of late recurrence.
“I had four chest drains in eighteen months. Every time: ‘spontaneous pneumothorax.’ I was 32 and otherwise healthy — it made no sense. I’d told three different doctors it always happened around my period and that I had endometriosis. Nobody connected it. It was only when I found Mr Scarci that someone actually took that information seriously. VATS found holes in my diaphragm. I’d never heard of catamenial pneumothorax before that appointment. Two years later, not a single episode.”
What a catamenial pneumothorax specialist provides that standard care does not
This condition requires specific surgical knowledge, a specific operative approach, and coordinated gynaecological care. This is not a standard pneumothorax referral.
Asks the right question
The single most important diagnostic step — asking whether each collapse coincides with the menstrual cycle — is almost never asked in A&E. A specialist consultation puts this at the centre of history-taking.
VATS with a specialist eye
VATS for catamenial pneumothorax requires systematic survey of the entire diaphragm and all pleural surfaces — not just the lung apex. Only a surgeon who knows to look finds the fenestrations present in 87% of cases.
Coordinated gynaecological care
Post-operative hormonal management prescribed by a gynaecologist experienced in endometriosis is the component most often absent when women are treated as if this is standard spontaneous pneumothorax.
Understanding of recurrence
Surgery alone carries a 20–32% recurrence rate. Understanding why this happens and how combined treatment reduces it requires specific knowledge of thoracic endometriosis — not just pneumothorax management.
Seen within days
Most patients are seen within one week of contact. For a condition that recurs monthly, a waiting list measured in months is a waiting list measured in collapses.
All major insurers accepted
Catamenial pneumothorax surgery is covered by all major UK private health insurers as a medically necessary procedure. Mr Scarci’s team handles pre-authorisation from the outset.
You’ve been through enough episodes. It’s time for the right diagnosis.
Mr Scarci reviews your full history with catamenial pneumothorax in mind — the timing, the side, the pattern. You leave with a plan that addresses both the surgical and hormonal components.
