Riverdale star Lili Reinhart has revealed her shock endometriosis diagnosis.

The American actress, 29, shared a series of photographs of herself in a hospital bed after getting keyhole surgery.

Endometriosis is a chronic condition that causes tissue similar to the lining of the uterus to grow in other locations inside the body, and can cause symptoms like intense period pain, heavy bleeding and pelvic pain, even infertility.

Watch the videos above.

Lili ReinhartRiverdale star Lili Reinhart has revealed her shock endometriosis diagnosis. (Instagram/@lilireinhart)

“Last week, I was officially diagnosed with endometriosis following laparoscopic surgery,” the star wrote in a candid post with her millions of followers on Instagram.

“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.

“Three hospital visits. Multiple urologists and gynecologists. And not one of them seriously considered endometriosis as the underlying cause of what I was experiencing.”

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Lili Reinhart“Last week, I was officially diagnosed with endometriosis following laparoscopic surgery.” (Instagram/@lilireinhart)

She spoke about how hard it was to get diagnosed, saying she saw two pelvic floor therapists and “pushed for an MRI on my own” before her diagnosis.

“At the same time, another gynecologist told me I ‘probably didn’t have endo’ and should just go on the pill,” she said.

She added, motivating fans to keep on top of their health: “I’m glad I trusted my body and listened to my gut and will continue advocating for others to do so.”

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The actress previously revealed her secret health battle, and said she was diagnosed with interstitial cystitis. (Variety via Getty Images)

The actress previously revealed her secret health battle, and said she was diagnosed with interstitial cystitis and has “a mysterious autoimmunity/inflammatory disease”.

She spoke about her health battle to Self, telling fans to keep on top of their health, trust their own instincts and to ”listen to your body” even when doctors are struggling to find a diagnosis.

“Listen to your body, and don’t take no for an answer. Don’t let a doctor tell you that nothing’s wrong when you know that there is,” she told the publication.

Reinhart, who has long been open about her battle with her mental health and depression, told the outlet she’d recently had COVID-19 at least three times.

The star said she also suffered an eating disorder and alopecia.

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