Lady Gaga has cancelled Born This Way Ball concert dates in Chicago, Detroit and Hamilton, Ontario due to severe joint pain.

"I barely know what to say," she wrote on her Facebook page yesterday. "I've been hiding a show injury and chronic pain for some time now, [and] over the past month it has worsened. I've been praying it would heal. I hid it from my staff. I didn't want to disappoint my amazing fans. However, after last night's performance I could not walk and still can't."

Gaga added that she has synovitis, which defined as severe inflammation of the joints. "I hope you can forgive me, as it is nearly impossible for me to forgive myself," she contineud. "I'm devastated & sad. It will hopefully heal as soon as possible. I hate this. I hate this so much. I love you and I'm sorry."

Get better!

Less than an hour after returning home from Brazil, Kim Kardashian, her sister Khloe, Kanye West, and mom Kris Jenner stopped by the doctor's office in Beverly Hills for a pre-natal checkup.

Kim started showing a few weeks ago, but she's still not ready to give up her designer duds for maternity clothes, as evident from the skintight leather pants she wore today. Kim looks great, but her baby bump could definitely use some breathing room! Wonder if she's going to find out the sex of the baby?

After a trip to the OB/gyn, Kimye stopped by Pinkberry for a sweet treat ... gotta satisfy those pregnancy cravings!

Halle Berry is one of the best hands-on Hollywood moms!

The Oscar-winning actress was in great spirits while walking adorable daughter Nahla to school. Love that smile.

There's a chance Olivier Martinez's fiancee will be starring in the upcoming flick X-Men: Days of Future Past, but the film's director, Bryan Singer, wouldn't say much. At a press conference, Singer said:

"I can't say. I don't know yet. And it's not necessarily a deal making aspect at all. I want to make sure it'll make sense."

We hope so!

Oh Vicky B, you never cease to amaze us!

Victoria Beckham and her daughter Harper hit Bergdorf Goodman for some shopping today following the debut of her lower priced line, VVB, and the British beauty did some self promotion by donning items from her own collection as she made her fashionable exit from the department store.

VB has been earning rave reviews for her collection during NY Fashion Week, so she must be thrilled!

How would the former Spice Girl describe her designs?

"Reflection, texture and simplicity in design were my starting points - and I have strived to keep true to the essence of the line while incorporating new finishes and fabrics. For me, it is the application of a refined quality within a mannish modernity that has proved to be such an exciting part of the design process this season. This has encouraged me to develop and enrich the collection for my customer," she explained of her inspiration.

Who knew Posh would be more famous for her style sense than for her singing?!

After checking out the sights in Rio de Janeiro and Vidgal with pal Will Smith, Kim Kardashian and Kanye West are back from their babymoon in Brazil! The couple quickly made their way through LAX, and they coordinated with black and white outfits. C'mon, you know they planned this!

Despite missing Sunday night's Grammys (Kanye won 3!) the lovebirds have been all over the place lately, and it doesn't look like Kim's slowing down anytime soon! Just a few minutes ago she tweeted, "HI NIGERIA! I'M COMING TO JOIN @DAREY FOR NIGERIA’S BIGGEST LOVE CONCERT #LLAM ON FEB 17TH AT EKO HOTEL. SEE YOU SOON!!!"

We're not sure if Kanye accidentally tweeted from her account, but seriously ... when was the last time she was in Los Angeles for more than a few days?!

The same Italian magazine that published topless photos of Kate Middleton last September has now gotten their hands on pictures the pregnant Duchess of Cambridge in a bikini while on vacation in Mustique.

St. James Palace has confirmed that Chi magazine has the pics, and they issued the following statement:

We are disappointed that photographs of the Duke and Duchess on a private holiday look likely to be published overseas. This is a clear breach of the couple’s right to privacy.

In September 2012, the British royal family took France's Closer magazine to court after they published the first topless photos of the duchess. A judge ruled in favor of the royal family, and the publication was banned from printing or selling the "highly intimate" photos.

Mila Kunis covers the March issue of Allure Magazine in nothing but a Marc Jacobs tee and undies, and while her interview isn't anywhere near as revealing, she does open up about beau Ashton Kutcher.

Prior to Ashton, Mila dated fellow Macaulay Culkin for eight years, and she reveals that the split well before the public found out. "For four years I was single. An amazing time. An amazing time. I love being single," she said with a smile. "You can go either way. You can be in a relationship. Or you could be having fun."

When Kunis is told it's interesting that she settled on a man she's known for years (she and Kutcher first met on the set of That 70s Show when he was 20 and she was 14), she replies, "People change. So who you knew years ago is not necessarily the person that you [know now] ... And who somebody was yesterday is very different from who they will be tomorrow."

But after making that statement about her beau, Mila declined to engage in further discussions about their relationship. When the interviewer showed her a photo of Ashton she said, "I didn't think this was going to be about my friends. Happily about myself! Not about who my friends are, who I'm dating, or who I may have ever dated. That’s not talking about myself!" But if it's someone she had a relationship with, it kinda is!

Click thru for another sexy shot of Mila...

Justin Timberlake and Jay-Z are reportedly planning a major stadium tour this summer, which will include 11 to 13 dates, according to sources for Rolling Stone.

Before performing at the Grammys on Sunday night, Timberlake chatted with the NY Post on the red carpet and said, "We're definitely going to go on tour ... I don't know how much I should say. It's going to be a lot of fun, I know that."

Jay-Z has performed with Justin several times for their hit new single "Suit & Tie", but there are no other details as to what sets would be like on the possible joint tour. Jay sang with JT during a pre-Super Bowl party in New Orleans earlier this month and he also joined the singer at this weekend's Grammy Awards.

Timberlake's new album The 20/20 Experience will be released on March 19th ... "Suit & Tie" is alright, but we really can't wait to hear more!