Sasha Pieterse has revealed the medical condition behind her weight gain - and the cruel abuse she has had to deal.
The 'Pretty Little Liars' actress admitted she was subject to nasty jibes from people who seemed "angry" after the star put on around 70 lbs over two years.
Speaking during rehearsal footage shown on 'Dancing With The Stars', she candidly said: "I gained 70-ish pounds over two years. It was really, really hurtful the way people reacted.
"People were saying stuff like, 'she's pregnant, you're fat.' They were angry, they were mad that I look like this."
However, a recent diagnosis of a hormone imbalance has hellped the star find comfort - and while she has suffered with one of the most difficult things she's "ever been through", having a label and reason for the weight gain made it easier to understand.
She added: "[It was] one of the hardest things I've ever been through. I had no idea what was going on and I didn't have any way of solving it.
"Very recently I was diagnosed with PCOS, Polycystic Ovary Syndrome, a hormone imbalance. Finally, I knew why this was happening to me."
Opening up to her professional dancing partner Gleb Savchenko, Sasha explained how appearing on 'Dancing With The Stars' has revitalised her, and allowed her to be herself.
She explained: "I think most importantly, I'm feeling like me again. Being on the show, I've lost over 15 pounds."
Meanwhile, the actress will be back on screens reprising her 'Pretty Little Liars' role of Alison DiLaurentis in a spin-off following the end of the show.
'The Perfectionists' will be adapted from a novel by author Sara Shepard, who also penned the book that inspired the original TV hit.