The 21-year-old actress updated fans on Monday's episode after sharing in September that she gained nearly 70 pounds over two years due to the hormonal disorder polycystic ovary syndrome.
"We're halfway through the competition and I've lost 37 pounds. It really is magical," she said prior to her performance.
Pieterse went public about her struggle with the disorder on the ABC reality competition's Sept. 26 episode, and said at the time she was down 15 pounds. She told viewers the show was aiding in her recovery.
"I'm feeling like me again," the star said. "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."
Pieterse dazzled during her rumba with partner Gleb Savchenko to "Kiss the Girl" from "The Little Mermaid" on Monday, but was ultimately eliminated from the competition. Savchenko praised the actress in subsequent Instagram posts.
"I want to thank my great partner @sashapieterse27 and my wonderful @dancingabc family and especially all my loyal fans for the support throughout #Season25," the dancer wrote Monday. "As always, it was the most memorable experience!"
"I'm so proud of @sashapieterse27 she really wanted to learn and has worked so hard so she was a dream partner I'm gutted this journey is over but it was great whilst it lasted #teamAteam," he added Tuesday.
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Pieterse is known for playing Alison DiLaurentis on "Pretty Little Liars," and will reprise the role in an upcoming spinoff, "The Perfectionists."
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