Pretty Little Liars star Sasha Pieterse is on Dancing with the Stars, and she made a big revelation on Tuesday’s show: She suffers from polycystic ovary syndrome (PCOS), which caused her to gain 70 pounds over two years.

Now, she says, she’s “feeling like me again” thanks to dancing.“ “Being on the show, I’ve lost over 15 pounds,” she said on Tuesday’s episode. “It’s not an easy road, but being able to focus on getting myself healthy again, and the fact that I’m seeing results, getting better is all I can ask for.” (Dance your way fit with High-Intensity Dance Cardio, the first-ever socanomics DVD!)

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When she was gaining weight, Sasha says people would say hurtful things about her online, like that she was “fat” or looked pregnant. “They were angry or mad that I looked like this,” she continued. “It was one of the hardest things I have ever been through.” Sasha told E! News that before she was diagnosed with the condition, which causes a hormonal imbalance, she “had no idea what was going on and I didn't have any way of solving it."

PCOS causes a woman to have enlarged ovaries with small cysts on the outer edges. It’s one of the most common hormonal endocrine disorders, and can affect up to 10 percent of women, according to the PCOS Foundation. Symptoms typically include irregular periods, infertility, excess hair growth on the face and chest, weight gain, and difficulty losing weight, the organization says.

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It’s kind of shocking that PCOS could cause someone to gain 70 pounds in two years, but women’s health expert Jennifer Wider, M.D., says it can happen. “PCOS is driven by male hormones or androgens that tend to cause weight gain in the abdominal area,” she says. “Women who have PCOS often complain of weight gain.”

PCOS can be treated with combination hormonal birth control pills and progestin therapy (which can be via the mini pill or an progestin-containing IUD). Once the condition is under control, a patient can “definitely” lose any excess weight they’ve gained due to PCOS, Wider says.

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Sasha’s story is scary but luckily, her PCOS seems to be under control. If you notice that you have sudden weight gain, hair growth in surprising places, or other signs of PCOS, talk to your ob-gyn. Your doctor should be able to conduct screenings to determine if you have the condition, and give advice on next steps.

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Korin Miller
Korin Miller is a freelance writer specializing in general wellness, sexual health and relationships, and lifestyle trends, with work appearing in Men’s Health, Women’s Health, Self, Glamour, and more. She has a master’s degree from American University, lives by the beach, and hopes to own a teacup pig and taco truck one day.