Getty Images North America 1 / 8
Getty Images North America 1 / 8

Molly Sims is still more than a month from giving birth to a baby boy, but she's already thinking about her pre-baby weight.

"It's very hard," she told In Touch magazine. "You spend the last two months being pregnant thinking, 'How am I going to get the weight off?'"

This is actually old hat for Molly, as this will be her third child, which is something she never thought would happen.

"I'm a bit older, so I just never thought it was going to happen. We were shocked," she said.

One thing that likely won't shock anyone is her determination to shed the baby weight after she gives birth. She's currently doing Pilates, yoga and some cardio. But, she said she tries not to work out too much because she gets hungry during workouts and craves "salt, turkey and dark chocolate."

The hardest part about being pregnant and having two young kids -- Brooks, 4, Scarlett, 19 months -- is "mommy guilt and time management."

"I've made it my priority to carve out time to spend with each of them separately," she said. "I went from having a schedule I thought was crazy to one that's even crazier. I went from taking 10-minute showers to 37-second showers."

On Tuesday, the beauty posted a video on her blog announcing that she was having a boy. In the video, her kids helped her open an oversized box that was filled with blue balloons.

"Brooks is really excited about having a baby boy," Molly said in the video. "He's already named it Jack and the Beanstalk Batman. That's his full name."

She added, "When they told my husband that we were having a boy, I swear he almost started crying."

On Wednesday, Molly shared photos on her blog of her kids painting her belly blue.

"So, the news is officially out! We are having a boy. I can't even begin to explain how excited we are…especially Scott. 2 boys and 1 girl? It's his dream!," she wrote.