THURSDAY, OCTOBER 16, 2008

Holly Madison, former 'number 1' girlfriend of Hugh Hefner has told In Touch magazine that not being able to have children with Hef was the main reason she left.

"I wanted to have kids," says Holly. "When that wasn't possible, I realized that I had to be honest with Hef and break it off...

"We tried for me to get pregnant by in vitro fertilization, because it wasn't going to happen the old-fashioned way."

The 28-year-old was featured on the Playboy Mansion reality show The Girls Next Door, alongside Hef's other live-in girlfriends Bridget Marquardt, 35, and Kendra Wilkinson, 23. While Holly says she "devoted 100 percent" of herself to the professional hedonist, she never quite got into the swing of his famed lifestyle.

"I'm not really into polygamy," she says. "That was never my thing. I think that's why I was looking to either have a kid or leave."

But the age difference between Holly and 82-year-old Hef proved to be the ultimate obstacle for the pair.

"When the IVF didn't work out after months of giving myself injections every day and feeling horrible, the clinic informed me it wasn't possible because he was too old," she says.

"Since we couldn't start a family I knew it wouldn't work," says Holly, who became depressed after the IVF failed.

Hef has dealt with the split by enlisting two new live-in girlfriends to join Bridget and Kendra — 19-year-old twins Kristina and Karissa Shannon.

And for her part, Holly is moving on as well.

"I would never be with a man who's that much older than me ever again."

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