Alison Sweeney also has a 3-year-old son

"The Biggest Loser's" Alison Sweeney has gained six pounds ... in the form of a baby.

The TV host and her husband, Dave Sanov, gained a daughter late Monday night, reports People.

"Both mommy and baby –- and daddy, too -– are doing well," says rep Carrie Simons. "It was a very easy delivery, and everybody is great."

The baby, named Megan Hope Sanov, weighed 6 lbs., 7 oz. at birth.

Sweeney, 31, was reportedly working on the NBC show until the bitter end and even rushed to the hospital in full hair and makeup from the set.

The couple already have a 3-year-old son, Ben.

A new episode of "Biggest Loser: Couples" airs Tuesday night on NBC.