Selena Gomez has revealed a scar on her inner thigh, which was left following a kidney transplant three years ago.

The 28-year-old pop star received the kidney from her friend Francia Raisa after suffering complications from the autoimmune disease lupus.

It was later revealed that Gomez nearly died due to complications from the surgery.

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When I got my kidney transplant, I remember it being very difficult at first showing my scar. I didn’t want it to be in photos, so I wore things that would cover it up. Now, more than ever, I feel confident in who I am and what I went through...and I’m proud of that. T - Congratulations on what you’re doing for women, launching @lamariette whose message is just that...all bodies are beautiful.

A post shared by Selena Gomez (@selenagomez) on Sep 24, 2020 at 9:57am PDT

She told fans she had previously been ashamed to let others see the scar, but now felt "proud" of her past and was ready to show it off.

The former Disney Channel star posted a photo on her official Instagram page, standing in front of an outside swimming pool in a baby blue swimming costume, with her hands above her head.

Gomez wrote: "When I got my kidney transplant, I remember it being very difficult at first showing my scar. I didn't want it to be in photos, so I wore things that would cover it up.

"Now, more than ever, I feel confident in who I am and what I went through...and I'm proud of that."

Fans were quick to comment on the symmetry between her scar and a tattoo on her left outer thigh, praising her for sharing the inspirational shot.

I'm very proud of Demi and Selena, the most bravest and strongest girls 🤍🖤 #DemiLovato #SelenaGomez pic.twitter.com/ELfHsIR9yc

— Dan 🦕 (@Dragonfly__1) September 24, 2020

She signed off her post, which was in support of her friend Theresa Mingus's fashion line, "all bodies are beautiful".

Gomez revealed she was diagnosed with the autoimmune disease lupus in 2015, and said she had "been through chemotherapy" in an attempt to cure it.

With lupus, the immune system (the body's defence system) turns against the body and produces too many antibodies - causing harm to organs and tissues, principally the kidneys and skin.

Organs are often damaged irreversibly, meaning many lupus sufferers have transplants.

Following her kidney transplant, Gomez posted pictures of her and Raisa in hospital beds holding hands, writing: "She gave me the ultimate gift and sacrifice by donating her kidney to me.

"I am incredibly blessed. I love you so much sis."

She also posted photos of scars on her stomach following the surgery.

Earlier this year, speaking on Miley Cyrus' Bright Minded Instagram series, Gomez revealed she had been diagnosed with bipolar disorder.

She said she had undergone treatment for anxiety and depression, adding that the bipolar diagnosis "doesn't scare me."