Megan Fox is a babe in blue!

The 26-year-old actress showed off her stunning post-baby bod in a Roland Mouret dress while appearing on The Tonight Show with Jay Leno. She had son Noel only two months ago!

Fox tells Leno, "Having an infant is difficult. It's a lot of work and I didn't hire any help because I overestimated my own abilities."

As for eventually hiring some help, Megan added:

    "I said to Brian, "we have to get a night nurse or we're going to get a divorce because someone's got to sleep in this house or we're going to kill each other."

We hear ya, Megan!