Priscilla Chan is not only a medical school graduate, she is now officially Mark Zuckerberg's wife.

Priscilla Chan married the Facebook founder and CEO in a surprise wedding on Saturday, surrounded by 100 close friends and family members. The low-key event took place in the backyard of their Palo Alto, Calif., home. The couple has been dating for nine years, after having met during their sophomore year at Harvard University.

The question on everyone's mind: What did she wear?!

Details on Priscilla Chan's wedding dress have finally emerged.

The 27-year-old bride wore a white lace gown, called Sky Between the Branches, by designer Claire Pettibone, according to People magazine. The ivory laser-cut floral dress is ornamented with matte sequins lined in silk, reported the magazine. It also features delicate cutouts in the lace overlay, a sheer back and a chapel-length train that fell over Chan's shoulders.

The dress retails for a modest $4,700 and is currently available on Pettibone's website. It falls in the mid-price range of the designer's offerings, which sell for as much as $7,000 and up. The dress is part of Pettibone's continuing bridal collection.

The L.A.-based designer was thrilled with how Priscilla Chan looked in her design.

She wore it with such grace, Pettibone told People magazine. Her gown seems to perfectly capture her personality -- understated and elegant with a touch of sparkle. It's a perfect blend of femininity and fashion.  

Pettibone has designed wedding dresses for the likes of Mad Men actress Elisabeth Moss, American Idol contestant Tamyra Gray and a bridesmaid dress worn by Cameron Diaz.

As for Priscilla Chan's ring, Mark Zuckerberg gave the blushing bride a simple ruby ring that he designed himself, according to Us Weekly. She did not see the ring until the ceremony.

Chan graduated on Monday from medical school at the University of California, San Francisco, and guests thought they were attending a surprise party to celebrate this graduation. Little did they know the couple had been planning the wedding for five months.

Guests ate family style from some of the couple's favorite Palo Alto eateries including Palo Alto Sol and Fuki Sushi, Us Weekly reported. Dessert was  L.A. Burdick handmade chocolate mice, whimsical delicacies popular for every occasion. The couple shared these on their first date.