"They were way too big, originally," the Modern Family star says of her bust. "But I didn't want to be disproportionate."
"I had the option to go even smaller," says the 18-year-old. "But I'm a curvy girl, and I didn’t want to change that. I love being a curvy girl."
For more from Winter – including her plans for after Modern Family – pick up the latest issue of PEOPLE, on newsstands Friday
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"I had the surgery because it bettered my life," she says. "It's important to talk about it because there are young girls suffering like I did – and there shouldn't be a stigma about it."