One party is just not enough these days. Jennifer Lopez's husband Marc Anthony threw her a surprise 40th birthday party called An Evening For Lola at the Edison Ballroom in New York City.

The marquee spelled out Lola (Anthony's nickname for Lopez) in gold embossing, the first hint that a fete was in store for the diva. After climbing from their car, the actress burst into tears of surprise as barricaded fans shrieked for her.

Jennifer looked stunning in a Grecian dress as she signed autographs before entering her own party. Alex O'Loughlin, Gayle King, Guadalupe Lopez, LA Reid, Leah Remini, Lisa Lopez, Liza Minnelli and Ricky Martin were among those helping Lopez celebrate turning 40.

Gallery Info: An Evening For Lola - A surprise 40th Birthday celebration for Jennifer Lopez

Click any thumbnail to view all 44 photos in the gallery:

It was an emotional day on set for Jennifer Lopez. Lopez had to break the news to co-star Alex O'Loughlin, her true love, about her being pregnant with twins by artificial inseminated, not in real life, but in her film. Things got a bit lighter on the set later in the day, when they filmed a date night scene.

Gallery Info: Jennifer Lopez filming The Back-Up Plan with co-star Alex O'Loughlin

Click any thumbnail to view all 79 photos in the gallery:

Twins, a husband, a football team, singing, acting. Jennifer Lopez has a lot on her plate, but the multi-hyphenate is ready to pile on more. She tells Extra, "I would love to have more kids. I don't know if we will. I don't know if that's in the cards for us. But we'll see."

Jennifer revealed that she loved staying home with her kids, but was ready to get back to work. She brought little Max and Emme to The Back-Up Plan set nearly every day. "They've been with me almost every day on the set. I don't think they realize what I do. Once in awhile, they look at the monitor and go, 'Mama.' They're just starting to talk."

Lopez plays a woman who is artificially inseminated on the same day she meets Mr. Right, and sports a fake belly bump for the film. "A bunch of us who have babies, we're like, 'It would be great when you are pregnant...you could take it off five times during the pregnancy, only for a half hour. Then you have to put it back on.' That would be awesome. It would be perfect. But you can't."

Wow. I feel like I've learned so much from Jennifer today. She's such a treasure.

Gallery Info: Jennifer Lopez, with Alex O'Loughlin, pushes a stroller with twin babies on the set of her new film The Back-Up Plan

Click any thumbnail to view all 27 photos in the gallery:

Jennifer Lopez has been hard a work the past few months filming her new film The Back-Up Plan. The romantic comedy follows Zoe, a woman who conceives twins through artificial insemination, and meets the perfect man on the same day. You sure this isn't more of a fantasy flick?

Jennifer has been looking fabulous on set. She looks especially good in the photos below. Not gonna lie, she and co-star Alex O'Loughlin look pretty fab together.

I hope that he Alex doesn't end up blaming her for ruining his career (really Ben Affleck, it's your fault too). To be fair, Alex and Jennifer are only dating in the movie. Maybe that's way most people should date her. Gotta love Jennifer Lopez.

Gallery Info: Jennifer Lopez and Alex O'Loughlin on the set of their film The Back-Up Plan.

Click any thumbnail to view all 57 photos in the gallery:

It was after she discovered a lump on the head of her twin daughter Emme at 3 weeks of age, that Jennifer Lopez (seen here filming a dining scene with Alex O'Loughlin on the set of her movie The Back-Up Plan) was motivated to form the Maribel Foundation.

The pop star explains, "We both got very nervous, and I just remember my heart sinking to my feet." Test results revealed that the baby girl was healthy, however Lopez was inspired to help less fortunate families who could not afford such medical services.

At that point, she teamed up with the Children's Hospital of Los Angeles to form the foundation to provide pediatric healthcare to those in need. Well, isn't she just a diva with a heart of gold.

Gallery Info: Jennifer Lopez with Alex O'Loughlin on the set of The Back Up Plan.

Click any thumbnail to view all 35 photos in the gallery:

Jennifer Lopez continues filming her latest movie The Back-Up Plan. She looked happy enough as she talked with director Alan Poul before getting dressed up for her night scene.

Jennifer, who wore a pair of wide-leg linen trousers and a baggy white top, spent the afternoon rehearsing lines before filming kicked off. She also seemed to be getting along well with the crew and co-star Alex O'Loughlin as she laughed her way through breaks.

The Back-Up Plan is a romantic comedy about a woman, Zoe (Jennifer), who conceives through artificial insemination, only to meet her soul mate on the same day.

Gallery Info: Jennifer Lopez with Alex O'Loughlin on the set of The Back-Up Plan

Click any thumbnail to view all 67 photos in the gallery: