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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)

Celebrity moms celebrate #BumpDay by showing off their pregnancy bellies

Suzy Byrne
Editor, Yahoo Entertainment

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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