‘It took 17 years to get an endometriosis diagnosis – by that point it was even in my lungs’

During almost two decades of experiencing excruciating pain that has driven her to A&E multiple times, Monica Thomas has been dismissed, accused of lying and “faking it”.

From the age of 15, the now-34-year old says she has faced a battle to find the cause of worsening pain in her pelvis, bowel and eventually her lung.

Not having her pain taken seriously even led her to question herself, until, finally, she got a diagnosis of endometriosis 17 years later.

“I’ve been accused of being a drug seeker, I’ve been accused of lying, I’ve just not been believed, I’ve genuinely felt crazy throughout this process,” she said.

Ms Thomas is one of 1.5 million women in the UK with the condition that causes cells similar to those found in the lining of the womb to grow elsewhere in the body. Symptoms can include pelvic pain, painful periods, heavy period bleeding, pain when going to the toilet or having sex, and fatigue.

Her experience of diagnosis problems comes as recent polling from the charity Endometriosis UK suggests the average woman waits nearly 10 years for a diagnosis – up from eight in 2020.

While the majority of women with endometriosis experience pain within the pelvic area, up to 12 per cent can experience it elsewhere in the body. In Ms Thomas’s case, when she gets a flare-up, she experiences it in her lungs and diaphragm.

She said: ‘It is a stabbing, sharp pain in my chest, [it feels] like my lungs are stuck – like a pulling sharp sensation…’

Her specific condition is called thoracic endometriosis and causes tissue in other parts of the body to build up and then shed, as it would in the womb during a woman’s period. It can result in chest pain, blood in the chest cavity and cause those who have it to cough up blood. In severe cases, it can lead to a collapsed lung.

Ms Thomas said the breakthrough in her diagnosis was a huge turning point.

“Throughout these years of going to A&E, I didn’t know what it was, I wasn’t diagnosed with endometriosis… I got to the point where I doubted myself so much.

“It got to the crunch point when I was told by [a health professional] that I was faking it. I was brought in by ambulance, and at the time I was really in pain and thought something serious was going on with me, one of the medical professionals came and said in front of me, ‘she’s always faking this.”

Ms Thomas finally got her diagnosis in 2024 of endometriosis and adenomyosis, a condition where the lining of the womb grows in the muscle. However, she said she faced further challenges when she asked doctors if the condition could also be causing her chest pain.

The response she claimed she received from one doctor was “endometrosis doesn’t grow in the chest”.

Ms Thomas said she was refused a referral for further investigation, so she turned to a private doctor, who found lesions in her diaphragm. She then underwent specialist tests to confirm the presence of thoracic endometriosis.

She now faces a further wait for treatment and has been told she might not have surgery to remove the tissue that is causing the pain for another year.

She said: “It’s already getting worse. It’s often just described as ‘bad periods’… it’s a whole body disease; it genuinely does affect the whole body.”

Speaking on The Independent’s Well Enough podcast, Dr Raj Arora said the condition was a complex one that is often misunderstood.

He said: “Endometriosis historically has been understood as a gynaecological condition, and it’s essentially where cells are similar. It’s not the same, but similar. So the lining of your uterus grows outside of your uterus.

“They can actually grow on your bladder, your bowels, even nerves, for example, the limbs, and they may even grow on your lungs. So, actually, although historically the condition has been seen as a gynaecological condition, it is quite complex, and now we are starting to see it more as a whole systemic condition, which, for me, is exactly where it should be placed.”

A Department of Health and Social Care spokesperson said: “Waiting nearly a decade for an endometriosis diagnosis is unacceptable. Stories like Monica’s show just how badly women with painful conditions have been let down.

“We are determined to change that. We are renewing the Women’s Health Strategy, improving training for new doctors and, through our 10-Year Health Plan, we are cutting waiting times for gynaecology services so women get diagnosed and treated sooner.

“Endometriosis will also be prioritised through NHS Online – a new online hospital service giving patients access to expert care from home.”