Happy #BumpDay! Olivia Wilde, Jaime King and More Show Off Their Bellies to Raise Awareness for Maternal Health

Nothing like baring your baby belly — especially when it’s for a great cause!

On Wednesday, Olivia Wilde, Jaime King, Vanessa Williams, Nicky Hilton Rothschild and more took to social media to support the second annual #BumpDay which, according to its website, was launched in 2015 in an effort to “help raise awareness about the need for maternal health care worldwide.

“Over 830 women die every day as a result of pregnancy-related causes,” the site continues, adding that most of these deaths could be prevented with access to quality maternal care.

“Join me today on #BumpDay to ask Congress to pass the #ReachAct so all moms have healthy pregnancies,” expectant mom Wilde, 32, wrote next to a pretty photo of her smiling self in a pink bikini.

Olivia Wilde/Instagram

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Last year‘s #BumpDay — an initiative backed by WhatToExpect.com, International Medical Corps, United Nations Foundation and 1,000 Days — saw huge successes over both Twitter and Instagram, trending at the top of both platforms.

The campaign is encouraging expectant moms, groups of moms (in settings like prenatal yoga classes and workplaces) and even dads to join in on the movement, with the latter group posing alongside bump-bearing loved ones.

“Clearly, there is no more pressing global issue affecting our entire future than the health of pregnant women around the world,” Heidi Murkoff, author of the What to Expect series, wrote in a 2015 blog for Huffington Post the week #BumpDay first launched. “Yet, unbelievably, there is no single day devoted to it.”

“Healthy futures start with healthy beginnings, and the health of the world’s mamas-to-be is linked inextricably to the health of our world,” Murkoff added. “We can shape that future, one mom, one bump, one baby at a time.”

— Jen Juneau