The couple, who met in the 2006 revival of A Chorus Line and began dating in 2008, already have a 2-year-old daughter named Gia.
© PA Images / Chris Pizzello/AP
Lopez told Extra: "I am the happiest father in the world. We cannot wait to welcome baby Lopez number two into our lives."
The gossip show, which Lopez co-hosts, surprised the former Saved By the Bell star with a baby shower to celebrate the news.
The X Factor USA host's daughter appeared during the surprise wearing a t-shirt bearing the words: "Big sister Gia."
Lopez and Mazza were married in Mexico in December.
Watch Mario Lopez and Courtney Mazza's baby announcement on Extra below:
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