Olivia Wilde and other famous moms support #BumpDay with sweet photos

It was for a very good cause that Olivia Wilde bared her baby bump on Wednesday (Aug. 3). The actress, who is expecting her second child with Jason Sudeikis, posted the snap on social media to celebrate #BumpDay, which has been working to raise awareness for maternal health care since launching in 2015.

Olivia, who can be seen rocking a pink bikini and a wide-brimmed sun hat in the snapshot, urged her fans to "Join me today on #BumpDay to ask Congress to pass the #ReachAct so all moms have healthy pregnancies," adding the hashtag "#bumpbumpbumpitupppp".

TAP TO VIEW GALLERYOlivia Wilde baby bump InstagramOlivia Wilde bared her tummy for #BumpDay

Olivia revealed her second pregnancy back in April, sharing a sweet snapshot of herself and two-year-old son Otis to announce the happy news.

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The 32-year-old wasn't the only famous face celebrating #BumpDay. Nicky Hilton Rothschild, who gave birth to daughter Lily Grace on 8 July, took to Instagram to share a beautiful photograph taken in her little girl's nursery before her arrival.

Nicky Hilton showing off her baby bump on InstagramNicky Hilton Rothschild shared a pregnancy snapshot in support of the campaign

"Every mother deserves a healthy pregnancy and safe delivery of her child," she wrote alongside. "Celebrate #BumpDay by posting your bump and supporting the #ReachAct."

Jaime King also posted a pregnancy photo, asking her followers to "please see how we can all support maternal heath in a greater way".

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According to BumpDay.org, "over 830 women die every day as a result of pregnancy-related causes". The organisation states that "most maternal deaths are preventable with access to prenatal care in pregnancy, skilled care during childbirth, and care and support in the weeks after childbirth".

Jaime King also showed her support

When the campaign was launched last year, Heidi Murkoff, author of the What To Expect series, wrote a blog for Huffington Post, urging mothers and moms-to-be to take part.

"Clearly there is no more pressing global issue affecting our entire future than the health of pregnant women around the world," she wrote. "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. We can shape that future, one mom, one bump, one baby at a time."

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