For expectant mamas heading on vacation, swimwear selection is always top of mind, but when you're heading to the beach — or even the backyard — you may want to celebrate the day wearing a two-piece swimsuit. Fifty percent of our readers  showed off their burgeoning bellies in a bikini while pregnant — and they're not alone. Take a look at some of our favorite expectant celebs who also sported bikinis while playing in the sun.
Molly Sims was happy as could be showing off her baby bump in a photo she captioned, "Sports Illustrated Swimsuit Preggers Edition."
Jaime King donned an itsy-bitsy bikini in her backyard.
Penelope Disick made herself at home atop her bikini-clad mom Kourtney Kardashian's baby bump while vacationing in the Hamptons.
Ali Larter  showed off the stunning view — and her belly — while on vacation.
A bikini-clad Hayden Panettiere  and her fiancé Wladimir Klitschko headed to the beach in Miami.
Jenna Dewan decorated her bump while wearing a bikini in St. Barts.
Pregnant Busy Philipps wears a bikini while hanging out with Michelle Williams  and Jason Segel  in Mexico.
On Mother's Day , Stacy Keibler posted this bikini picture of her baby bump.
Source: Instagram user stacykeibler 
Shakira  showed off her full, pregnant belly just before giving birth to baby Milan.
Source: Twitter user shakira 
Vanessa Lachey shared a beautiful sunset bikini photo — taken by her husband, Nick — while pregnant with Camden.
Source: Twitter user VanessaLachey 
Kourtney Kardashian wore a bikini while pregnant with little Penelope.
Early in her pregnancy, Holly Madison did a Las Vegas photo shoot in a red checked bikini.
Minnie Driver  gave her pregnant belly a little sun during the final days of her pregnancy.
Camila Alves sported a bikini to spend the afternoon strolling the beach.
Carla Bruni wasn't shy about baring her bump in a tiny bikini with her husband, then-French President Nicolas Sarkozy, in the French resort town of Fort de Brégancon.
Jenna Dewan showed off her pregnant belly during a vacation to St. Barts in early 2013.
Tori Spelling  was spotted taking a walk on the beach with her family while pregnant with baby Hattie. The now mama of four has said she's proud to show off her baby belly in a bikini.
Shiri Appleby shared a picture of herself on the beach during her final month of pregnancy.
David Beckham  snapped a picture of wife Victoria relaxing during the final days of her pregnancy with baby Harper.
Jessica Alba  showed off her growing belly while vacationing in Mexico .
Jessica Simpson  showed off her second baby belly with a selfie portrait while vacationing in Hawaii.
Elsa Pataky showed off her baby bump while hitting the water in St. Barts.
Kim Kardashian  showed off her baby body in DuJour magazine's Spring issue.
Gisele Bündchen took her bump down to Miami for a weekend getaway with husband Tom Brady  while expecting baby number two. She rocked an animal-print bikini on the beach and a large hat to shield her face from the sun.
Britney Spears  showed off her growing bump on the beach in Miami when pregnant with Jayden James.
Songstress Paulina Rubio showed off her growing bump in Malaga, Spain.
Nicole Richie  flaunted her bikini body in Hawaii while pregnant with Harlow in 2007.
Alicia Keys  wore a tiny bikini while celebrating her honeymoon on a yacht  off the coast of France.
Charlotte Church chose a bikini with boy shorts during a day at the beach back in 2007.
Toni Collette toweled off her expectant bikini body just weeks before delivering in Sydney.
A 41-year-old Uma Thurman  showed off her growing bump in a black bikini. She was expecting her third child, her first with her long-term partner Arpad Busson, a London-based financier.
Alessandra Ambrosio shared a picture of herself pregnant and in a bikini on the beach with her daughter Anja.
A newly pregnant Ashlee Simpson  took to the beach in a bikini while honeymooning with Pete Wentz  in the Caribbean.
Former Spice Girl Melanie Brown  slipped into a white bikini to hang out at the pool  with her husband.
Bethenny Frankel donned a two-piece bathing suit during her honeymoon in St. Barts .
Kristin Cavallari  shared a poolside snap, showing off her baby bump in a bikini. In another photo, she posed with her bikini-clad friends, writing, "Had the best weekend for @char_major 's bachelorette! Even though I was the first one in bed it was a blast."
Elsa Pataky decorated her baby bump while on set.