Olivia Wilde and Jason Sudeikis
When it comes to lending her name for a cause, Olivia Wilde
doesn't take that lightly.
"I would never expect people to follow every piece of advice that I offer," admits Wilde. "But when there's a cause that really needs a swell of public effort, I'm very comfortable putting that out there and encouraging people to become involved."
For years before becoming a Revlon brand ambassador
the actress, 30, has chosen to walk in the Entertainment Industry Foundation's Revlon Run/Walk, which raises money for the fight against women's cancers.
Last year's event holds a place especially close to the actress's heart.
"I walked with my mom and my soon-to-be mother-in-law [Kathryn] who is a cancer survivor," she tells PEOPLE. Wilde is engaged to actor
Jason Sudeikis. "It was really wonderful to be able to do that with her."
While Wilde's impending spring arrival of a baby boy
will keep her from participating physically in this year's walk, she vows to return next year. "I will absolutely run next year," she says with a laugh. However, the baby on the way has changed Wilde's outlook on what's important.
"I've always felt a certain responsibility to future generations and we're supposed to leave the world better than how we found it," she says. "But certainly now being a mom, I feel an even greater shifting of perspective away from my own ego and shifting outward."
The 21st annual EIF Revlon Run/Walk for Women will take place in both Los Angeles and New York. Revlon Brand Ambassador Emma Stone will host the 2014 event in New York on Saturday, May 3rd and Halle Berry
and Christina Applegate
will host in Los Angeles on Saturday, May 10th.
For more information visit RevlonRunWalk.org or by calling the event hotline at 855-434-3779.
And for more on why Wilde was inspired to join the fight against cancer and a look at PEOPLE's new feature 'Why I Care,' pick up this week's issue on newsstands Friday.