Nearly two weeks in their married life, Ashlee Simpson and Pete Wentz finally came out about the rumored pregnancy and explained why they chose to wait so long.

The celebrity couple, who tied the knot on May 17, a year and a half after they started dating, released a statement on Wentz's site confirming that they are expecting their first child.

"While many have speculated about this, we wanted to wait until after the first trimester to officially confirm that we are expecting our first child," Ashlee, 23, and Pete, 28, wrote. "This is truly the most joyous time in our lives and we are excited to share the happy news and start our family."

Wentz had already told Ryan Seacrest on his radio show immediately after the wedding that Ashlee was going to take his name, and now she explained that she will go by Ashlee Wentz in private, and Ashlee Simpson-Wentz professionally.

"I think that that's something that a woman should do when they're marrying a man," Simpson-Wentz told People. "It's a tradition that I think is a great tradition."

And just like a supporting husband he is, Pete encouraged Ashlee to take all these decisions on her own, saying he wants her " to do these kinds of things the way she wants to do them."

Ashlee Simpson, who is the younger sister of Jessica Simpson, released her latest album, "Bittersweet World," last month. It peaked at No. 4 on the Billboard 200 in its first week, and tracks have logged more than 19 million plays on her MySpace page.