It will be the first child for the Spears-Federline couple. Kevin Federline is already the father of two children from previous relationships.
Spears made the big announcement to her fans on her internet site. Her agent also confirmed the news.
The couple were married last September. During the past few months, the media have been speculating that the singer was pregnant, noting that her face had become rounder.
The star also revealed recently that she’d like to become a mother.
The last album by the singer has sold nearly 1 million copies so far.