05/30/2012 01:23 pm ET Updated Dec 06, 2017

January Jones Talks Fat Betty, Julianna Margulies On Being 'The Good Wife' And More Drama Actress Confessions

January Jones became Fat Betty for a reason. When the actress started Season 5 of "Mad Men," she was eight months pregnant. By the time filming the season had wrapped, she had a five month old. In an effort to conceal her pregnancy, her character Betty put on the pounds.

"I was in seven hours of prosthetics every morning, trying to rip off a fake chest piece so I could breastfeed," Jones said in a new roundtable interview with The Hollywood Reporter. Jones, Julianna Margulies of "The Good Wife," Claire Danes of "Homeland," Kyra Sedgwick of "The Closer," Emmy Rossum of "Shameless" and Mireille Enos of "The Killing" all sat down for an interview with THR to discuss being leading dramatic actresses on TV.

When asked about the Fat Betty direction, Jones said she "loved it." "I didn't want to try to hide it. I thought it would become comical and weird," Jones said. "I also didn't want to have the character become pregnant because it just wouldn't make sense -- she had just had one. And I thought it would be something fun, not realizing it was going to be a pain ... It was definitely difficult, but I love what [Matt Weiner] did with the character's story. Everyone likes a challenge."

Fat Betty became an internet sensation and Jones has heard about the @FatBettyFrancis Twitter account. "That's crazy," she said.

Margulies said she thought the Fat Betty twist was "awesome." "I thought it was so brave," she said. "And great."

Jones went on to say her grandfather said she looked "a bit fuller, but still beautiful," thinking it was all pregnancy weight. "I thought I was watching Eddie Murphy in 'The Klumps' ... I was like, 'My career is over,'" she said with a laugh. Jones didn't watch the episode ahead of air and admitted it took her a while to get through it.

As for her challenges on "The Good Wife," Margulies said, "As much as I'd like to pretend it's an ensemble, it's not.

"It's 'The Good Wife,' and if the good wife goes down, there's no show," she said with a laugh. "My problem is, I'm not a squeaky wheel ... I'm a worker; I can wait tables. So I have this idea that I'm one of the crew, but the problem is I have to perform and have to be there two hours before the crew gets there and then work two hours when everyone goes home ... So my biggest challenge has been to say, 'Guys, guess what? I can't be in the background of so-and-so's scene,' because that would give me two hours with my kid. Or, how about an hour to sleep, go to the gym. Or learn a line or two. Don't just use me because I'm here all the time. I have to prepare and have a life. So that's been my hardest challenge, hopefully in Season 4 -- I'll be in a court scene for 14 hours without a line and that's craziness to me ... So they're going to work on that."

Watch the full, uncensored THR interview below and click over to THR for more from January Jones, Julianna Margulies, Claire Danes, Kyra Sedgwick, Emmy Rossum and Mireille Enos.

For more photos from "Mad Men" Season 5, click through the slideshow below:

Mad Men Photos