Credit: Albert Michael/

Denise Richards hasn't always been happy with her body. In the new issue of Us Weekly (out now), the 40-year-old actress opens up about her series of botched boob jobs -- and why she decided to show them off in Playboy.

"When I was 19, a doctor put in bigger implants than what I asked for. I was in such a hurry to get them that I didn't research my doctor," Richards says. "I just thought because they're a plastic surgeon, they must be good. You have to be your advocate for your own body and ask 100 questions."

When she met with another surgeon to have them corrected, the doctor gave her even larger implants. "I felt very vulnerable," she tells Us. "I was getting ready to film [1998's] Wild Things, and I didn't want to get into a lawsuit with some plastic surgeon. It wasn't right what the doctor did, but it is what it is."

So why did the Real Girl Next Door author decide to doff her top for Playboy in 2004? "A couple reasons: I wanted to encourage women that it's OK to embrace your sexuality even though you're a mom," Richards explains. "At the same time, I was having some problems in my marriage [to Charlie Sheen] and I didn't feel sexy and felt I had to prove something."

The Blue Mountain State actress -- who recently adopted 6-week-old daughter Eloise Joni -- adds that she's happy with her current breast size.

"This is the size I wanted them to look at 19! There's a long investment with breast implants. They're not going to last a lifetime and things can go wrong," she tells Us. "I'm happy with them now, but in a year that could change."

For more revelations from Richards -- including her tumultuous relationship with Sheen, her mother's battle with cancer, her decision to adopt, and much, much more -- pick up the new issue of Us Weekly, out now!