Jennifer Lopez: "I Don't Know if I'm Going to Have Kids Again"

Jennifer Lopez says she wasn't worried that she wasn't able to get pregnant quickly.

"We knew nothing was wrong with either one of us I had been checked, and [my husband Marc Anthony] had kids already," she tells the October issue of Elle. "I knew something's not ready here, in my head or in my life, and when it is, I know it's going to happen."

But she says she knew instantly when she was pregnant one day while sitting down for hair and makeup.

"I felt a flutter. The weirdest little ... flourish," she recalls. "My makeup artist said, 'Whats the matter?' I didn't say anything, but in my head, I was like, 'I have life inside me!'"

See what Jennifer Lopez looked like pregnant.

Following weeks of speculation, she announced she was expecting during a Miami stop on her El Cantante Tour concert in November 2007.

"While pregnant, we came off tour and I said [to Anthony], 'I did the superwoman thing, I finished the tour now I need you to take care of me. I love doing things for you; if I'm not cooking, then I'm picking out a shirt.'

"'But this is the first time in my life where I'm just going to be a little bit selfish. I don't know if I'm going to have kids again, so I want it to be a beautiful experience. I don't want to have any drama. I want to just be smiling every day.'"

To remember her pregnancy with twins Max and Emme, she commissioned a book of photos of herself for Anthony two weeks before giving birth.

"I was like, 'How am I going to rock this moment of my life?'" Lopez says. "I felt very womanly. Marc was in a dream. He loved it."

Look back at Jennifer Lopez's fashion highs and lows.

Next up for Lopez: She is competing in her first triathlon, which takes place Sept. 14 in Malibu and benefits Children's Hospital Los Angeles.

"I feel great," she recently told Good Morning America. "I have more energy I'm proud of myself."