Celebrity moms celebrate #BumpDay by showing off their pregnancy bellies

Suzy Byrne
Editor, Yahoo Entertainment & Lifestyle

Baby bumps are beautiful — and they were on full display on September 13 for the third annual #BumpDay.

The event was started by the website What to Expect to help raise awareness about the need for maternal health care worldwide, and celebrities were happy to participate by sharing snapshots from their pregnancies — past and present. And there was even a birth announcement. Click on the photos above to see the beautiful baby bumps.

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January Jones

#BumpDay coincided with the sixth birthday of the Mad Men alum’s son, Xander, so she shared an artsy throwback photo of herself swimming while completely nude and bumpin’. “Happy day of birth to my son, my whole heart,” wrote the single mama. (Photo: January Jones via Instagram)

Behati Prinsloo

The Victoria’s Secret stunner, who is married to Adam Levine, announced their second joint production. “ROUND 2…..” she wrote. Their daughter, Dusty Rose, will turn 1 this month. (Photo: Behati Prinsloo via Instagram)

Heidi Klum

The America’s Got Talent and Project Runway judge knows about bumps after having four children. This shot was taken in 2009, when she was expecting her youngest child, Lou. (Photo: Heidi Klum via Instagram)

Eniko Hart

Kevin Hart can’t wait to be a dad again. His wife, Eniko, shared this sweet shot of him cuddling her belly, writing, “#BumpDay” with an emoji heart. The comedic actor is already a dad of two with his first wife. (Photo: Eniko Hart via Instagram)

Jaime Pressley

Earlier this summer, the My Name Is Earl alum announced she’s expecting twins with her boyfriend, Hamzi Hijazi. The actress, who already has a 10-year-old son, posted a photo of her twin bump and shared a factoid: “830 women a day die worldwide from preventable issues during pregnancy. A healthy pregnancy can set a child up for a healthy future.” (Photo: Jaime Pressley via Instagram)

Hillary Scott

The Lady Antebellum songstress gave away the fact that she’s expecting twins by using two baby emojis in her #bumpday post. She wrote, “In honor of #bumpday, here’s my bump. Encouraging all the expectant mamas out there to take care of you and your baby(ies)! #maternalhealth is SO important!” (Photo: Hillary Scott via Instagram)

Sienna Miller

The Factory Girl actress, who is mom to 5-year-old Marlowe, has just two photos on her Instagram — and this is now one of them. “The goal of ending preventable child and maternal deaths is within reach,” she wrote. “Here’s me and my Marley bump to celebrate! #bumpday.” (Photo: Sienna Miller via Instagram)

Amanda Seyfried

The Mamma Mia! actress loves her privacy and has no plans to divulge the name of her daughter, whom she welcomed in March. However, she did share a snapshot from her pregnancy — from the 27-week mark. “Every mom deserves a safe, healthy pregnancy, and every baby deserves a fair shot at life,” she wrote, posting with this beach pic. “By donating to the What to Expect Healthy Birth Project of the International Medical Corps this #BumpDay, you can help make that happen.” (Photo: Amanda Seyfried via Instagram)

Savannah Guthrie

The Today show personality, who has two kids, showed off her bump — and the woman who gave her life. “On this #bumpday thinking of the mama who carried me — and the privilege of carrying my babies. Support healthy moms and pregnancies!” she wrote. (Photo: Savannah Guthrie via Instagram)

Bar Refaeli

Bar Refaeli is on a timetable similar to Behati Prinsloo’s. She welcomed a daughter, Liv, in August 2016, and has another on the way. “Happy #BumpDay,” she wrote with this bare-belly pic. “Post your bump to raise awareness about the need for maternal healthcare worldwide.” (Photo: Bar Refaeli via Instagram)