Lopez plays a woman who decides she wants to have a baby through artificial insemination -- her "back-up plan" for starting a family. However, on the same day she receives the treatment, she finds the love of her life. Will their love survive her pregnancy?
Lopez said the part came along at the perfect time -- following the birth of her twins, Max and Emme, in 2008.
"I read the script. I was still trying to lose baby weight. I was like, 'This is funny.' ... The woman who wrote it had just gone through a pregnancy. So it's very accurate."
Was Lopez's husband Marc Anthony as supportive as the male lead in "The Back-Up Plan" when she was pregnant in real-life?
Lopez said he was "really awesome."
She added, "I mean, it's hard. The movie guys, they're like -- it's a little fairy tale. But seriously, he did really well. I remember having a talk with him, because we were on tour while I was pregnant and I said, 'You know what, Marc, I don't know if I'll ever be pregnant again in my life. I want this to be beautiful. You're really going to have to suck it up. You're just going to have to help me make this the most beautiful time and just put up with all of my stuff that happens.' He was like, OK.'"
For more on Lopez's family, career, and the advice she has for "Early Show" co-anchor Maggie Rodriguez, who is expecting her first son, click on the video below.
CBS Films' "The Back-Up Plan" is in theaters Friday.
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