Heidi Klum: Her Amazing Body Evolution

 Splash News; Alexander Tamargo/Getty; Steve Granitz/WireImage.com

While Heidi Klum's relationship status officially changed to “separated” on Monday, one thing that will undoubtedly remain the same for many more years is her incredible physique.

After four(!) kids the supermodel mom, 38, still looks as hot in a bikini as she did the first time she walked at the Victoria's Secret Fashion Show back in 1998.

Klum, who famously returned to the runway just two months after giving birth to son Henry in 2005, admitted that bouncing back post baby gets harder with age.

"Everything changes when you get older. It was different when I was 31 with the first one. Now, being 36 with the fourth one [daughter Lou], it's different." she told Us in 2009.

"For me, it always works to get back into it immediately," she said. "I think that if you wait too long, it kind of sticks on and it stays there forever. I have to be motivated."

PHOTOS: Heidi and other supermodel moms

Click through to see her most memorable body moments through the years.

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