Bikini

Kim Kardashian gave birth to a baby girl on Saturday, but just five days before delivering her first child, she was lounging poolside. Kim showed off her pregnant stomach in a skimpy bikini while hanging out at a spa in LA with friends, including Robin Antin and makeup artist Joyce Bonelli. The ladies snacked on a fruit and cheese plate during their three-and-a-half-hour stay, and while Robin and Joyce drank cocktails, Kim sipped on pink lemonade. The sunny afternoon wasn't the first time Kim flaunted her baby bump in a bikini during her pregnancy, since we also saw her in a two-piece during her family getaway to Greece back in April.

Kim and her boyfriend, Kanye West, may have welcomed their daughter a little earlier than her expected July arrival, but Kim seems to be enjoying motherhood already. She sent an email to Ryan Seacrest proclaiming that "It's so crazy!" and her sister Khloé shared that both "mommy and baby are healthy & resting." Kim has yet to reveal the baby's name, though sources say that she and Kanye are close to picking a moniker for their little one.

Ashley Greene and Vanessa Hudgens showed off their bikini bodies — and athleticism — at Oakley's Learn to Ride event in Bali, Indonesia, today. The ladies both hopped on surfboards to catch a few waves at the event, which serves to promote the sport of surfing. Ashley and Vanessa were sharing the perfect conditions with pro surfers since the event coincided with Oakley's Pro Bali surf competition as well. Although Ashley was able to successfully ride the waves, she did not escape the day without injury. She shared a picture of her leg, which was covered in scrapes, on her Twitter account, writing, "War wound from surfing today with Oakley. The reef ate me up." While Ashley and Vanessa were enthusiastic to try their hand at the water sport, the girls did find time to relax and soak in the Indonesian rays on a boat during the day as well.

Anna Kournikova showed off her bikini body when she joined Enrique Iglesias for a boat outing in Miami earlier this week. Enrique wasn't home for long as he soon traveled out to California to join Jennifer Lopez, Marc Anthony, and Chris Brown at Pitbull's concert at the Hollywood Bowl. Pitbull isn't the only star who had a party recently, as Anna celebrated her 32nd birthday earlier this month. She revealed on her Facebook page that she "had a nice relaxing day" with her friends and family.

Summer typically means a lot of time spent outdoors, and there's no one who knows more about what's it like to work up a sweat in the sun than athletes. To celebrate the official start of Summer at the end of this week, we're looking at a few of the best beach and pool moments from our favorite sports stars — you don't have to be an avid sports fan to like these celebrities! Click through to see Serena Williams, David Beckham, Ryan Lochte, and more athletes let loose when they're not working on their game.

Mariah Carey wore two different tiny swimsuits while filming in Southern Italy with fellow recording artist Miguel yesterday. The pop icon showed off her fit physique when she shared a photo collage of herself in a black cutout monokini on Twitter with the caption, "Behind the scenes on set with @MiguelUnlimited!! Coming soon." As part of the shoot, Mariah and Miguel went swimming in the blue grotto, off the island of Capri, and hopped on a yacht after climbing out of the water. The duo have been spending time together since collaborating on the song "Beautiful," which was released last month and is a track off Mariah's highly anticipated 13th studio album. The album, the official title of which has yet to be released, will drop July 23.

Much of the hype may be due to Mariah's frequent Facebook, Twitter, and Instagram teases. While she announced the album release date on her personal accounts, Mariah also took to Instagram yesterday to share a personal snap of herself in blue waters with the caption: "A much needed splash after hours pon de mic singing for my beautiful lambily." In the post, she was addressing her fan base and revealed that her new work encompasses "three years of my soul." Mariah has returned to song-making after announcing last month that she will be not be returning for the next season of Fox's American Idol.

Serena Williams donned a bikini when she hit the beach on Saturday with a group of friends in Miami. She is fresh off her win at the French Open last week, having defeated Maria Sharapova in the finals in Paris. Serena shared her trip to the beach on her Twitter account, tweeting that she was at the Soho House in Miami and posting playful shots of herself lying out on a chaise. She is getting in her vacation time before she heads back to the court in London for the 2013 Wimbledon Championships on June 24. Serena is currently the reigning champion at Wimbledon, having won the Women's Singles and the Women's Doubles alongside sister Venus Williams last year. If looking at Serena's toned figure is getting you in the mood to work out, be sure to check out our guide on how to get Serena Williams's abs.

Cameron Diaz and Leslie Mann covered up while filming a beach scene for The Other Woman with a bikini-clad Kate Upton in the Hamptons yesterday. Cameron wore a white two-piece but protected herself from the sun with a white button-up shirt and a panama hat, while Leslie donned a colorful costume. Last Wednesday, Kate Upton wore a skimpy bikini while filming a PDA scene with her costar Nikolaj Coster-Waldau on the sand. Meanwhile, on Monday, Cameron took a break from filming out in Long Island to travel back into NYC to meet up with her celebrity friends and attend Stella McCartney's Resort 2014 presentation at Jefferson Market.