Jaime Pressly has made it official: She's pregnant.

"I'm four months pregnant! I'm making it official tonight for the first time," the 29-year-old actress told Jay Leno on NBC's "The Tonight Show" on Wednesday.

The blond bombshell, known for her Emmy-nominated role as the trash-talking Joy on NBC's "My Name Is Earl," and disc jockey Eric Cubiche became engaged last month. They had been dating for about 18 months.

Pressly said she knows the baby is a boy.

"I'm healthy, the baby's healthy. We're good," she said.