'Grey's Anatomy's' Sarah Drew opens up about daughter's premature birth

Grey's Anatomy star Sarah Drew had a dramatic episode in real life when she gave birth prematurely last month. ET's Brooke Anderson visited the actress at her home to see how baby Hannah is doing now.

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"[Hannah] was whisked away very soon after," Sarah told Brooke. "I only got to hold her for a couple of minutes and then they tested her. I had gestational diabetes, so they tested her blood and they realized there was something wrong with her breathing, and she was actually in a NICU (neonatal intensive-care unit) for 11 days."

Sarah and her husband of 12 years, Peter Lanfer, were already parents to 3-year-old son Micah, and announced that they were expecting their second child in July. Hannah, who was just 6 pounds, 13 ounces at birth, is a healthy 10 pounds today.

"Basically she just needed a little more time to cook," Sarah said. "She was having really shallow breath and they needed to give her oxygen. She would just stop breathing and then they'd have to kind of stimulate her to get her to start breathing again."

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After Hannah's health scare, Sarah went through a similar experience at work on Grey's.

"My character [Dr. April Kepner] was going through some serious pregnancy complications on the show and having literally just lived through that stuff emotionally almost in a way prepared me for having to live through something that was not as bad as what's going on with the show, but was still dramatic and intense and emotional and all of those things," Sarah said.

Grey's Anatomyreturns to ABC on Thursday at 8 p.m. ET/PT.

Drew's evolving look throughout her many years of fame: