03/12/2008 at 04:00 PM EDT
Elisabeth Röhm is already planning her road back to pre-baby fitness for when she gives birth next month.
"I'm gonna run like Forrest Gump!" Röhm, who is expecting a girl, said Sunday in Los Angeles. "I definitely plan on doing NutriFit and running my ass off."
Over the weekend, the former Law & Order
star, 34, practiced her storybook reading skills for an audience of children at John Varvato's Stuart House Benefit in Los Angeles – something she'll be doing very soon at home.
"[My daughter] is due April 28
– my birthday!" said Röhm. "I'm willing to give up my birthday to her."
The is the first child for Röhm and her fiancé, entrepreneur Ron Wooster, who plan to wed in September. But so far, being an expectant mom has been easier than she imagined.
"My only humbling moments are when I have to grab onto the banister of my staircase and hoist myself up," she said. "Other than that it's been a breeze."
– Kimberly Lansing