Alessandra Ambrosio is working her baby bump like she works the Victoria's Secret runway!

The Brazilian beauty celebrated her 31st birthday Wednesday with some fun in the sun. Clad in a printed two-piece bikini, the pregnant supermodel proudly strutted along the sands with her bump on full display.

"Thank you all for the wonderful birthday wishes!!! Have a great weekend everybody!" she posted on her official Facebook page along with the pic above.

The baby-to-be will be the second for Ambrosio and California businessman Jamie Mazur, her longtime fiance, who are already parents to daughter Anja, 3.

"Family is the most important thing for me and I'm thrilled to be adding to the family," Ambrosio told Us Weekly in September in an exclusive statement. "I'm fortunate to have a loving and supportive family. It's a blessing that it will soon be growing."

In terms of other pregnant celebs and their bathing suit choices, the Victoria's Secret Angel is not alone in opting for a skimpy two-piece.

In late March, Kourtney Kardashian wasn't shy about revealing her very pregnant bod in a sexy tie-dyed bikini while on vacation with her family in the Dominican Republic.

Ebbing on the more conservative side, Reese Witherspoon hit the beach with her family in Costa Rica last week sporting a black one-piece bathing suit that covered up her tiny baby bump.