Lili Reinhart revealed she was diagnosed with endometriosis after doctors constantly dismissed her symptoms.

On Thursday, Dec, 11, the Riverdale actress posted photos on Instagram from a hospital bed showing her stomach after undergoing laparoscopic surgery. The 29-year-old shared that last week, she was diagnosed with endometriosis, a reproductive condition in which uterine tissue grows outside of the uterus, causing cramping and chronic pain.

“Last year, I saw a urogynecologist and was diagnosed with interstitial cystitis. I was told there was no cure—and no lasting relief—for my symptoms,” she wrote. “Three hospital visits. Multiple urologists and gynecologists. And not one of them seriously considered endometriosis as the underlying cause of what I was experiencing.”

“It wasn’t until I worked with two different pelvic floor therapists that the word endometriosis was even mentioned to me as a possible source of my pain,” she said.

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Reinhart said that she pushed for an MRI on her own, which ultimately led to her being diagnosed with adenomyosis, a type of endometriosis that only occurs in the uterus. 

“I met with an endometriosis specialist who helped me decide that laparoscopic surgery was the next step I wanted to take — while, at the same time, another gynecologist told me I ‘probably didn’t have endo’ and should just go on the pill,” she continued.

“I’m glad I trusted my body and listened to my gut and will continue advocating for others to do so,” the actress said. “(Endometriosis is an extremely misunderstood disease, leaving often a 4-11 year gap between symptoms and a definitive surgical diagnosis. It’s estimated 1 in 10 people with uteruses have endo according to the World Health Organization.)”

In addition to the hospital photos, Reinhart shared a picture of her holding a piece of paper that says, “Believing women’s pain shouldn’t be REVOLUTIONARY.” She also tagged the Endometriosis Foundation of America. 

Reinhart also posted a hospital selfie on her Instagram Stories, sharing how validating it felt to finally have answers about her health.

“I don't remember taking this horrible photo. But I think I wanted to capture a moment of post-surgery validation,” she wrote. “The second I saw my doctor I asked, ‘did you find it?’ And he said, ‘We found endo.’ And I felt so validated and relieved that I chose to listen to my body and pursue this surgery.”

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Earlier this year, Reinhart opened up about her health struggles and how she was searching for answers while dealing with an unknown illness. The Hustlers star told her social media followers that her grandmother’s experience with doctors is what made her so adamant about advocating for her own health.

“My grandmother was ignored by doctors for months when exhibiting clear symptoms of cancer,” she said back in January. “And it was only after her own strength and advocacy for herself that she was given a blood test that diagnosed her. And by then, the cancer had spread.” 

“The most important thing I have taken away from this experience is the absolute need to advocate for your own health,” she added. “Do not let a doctor gaslight you or diminish your pain.”

Reinhart joins a list of celebrities who have talked openly about their experiences with endometriosis. Bindi Irwin, Lena Dunham, Halsey, Julianne Hough, Amy Schumer and Padma Lakshmi have also shared their struggles in the past.