The news came along with an announcement for the dates of the singer's upcoming Cry Pretty tour, which kicks off on May 1, 2019.
"We are over the moon and so excited" said Underwood, 35, adding that she's glad son Isaiah, 3, will finally have another sibling.More news: Mendocino Complex now California's largest wildfire in history
Well, it turns out she has a very good reason for the delay - it's not easy to tour when you're several months pregnant or caring for a brand new baby! The album is set for release in September, but she told fans she won't begin touring until May 2019 because of her baby news.
Underwood and Fisher, a former National Hockey League player for Ottawa, Canada, and Nashville, Tennessee, have a 3-year-old son, Isaiah.
Underwood met former Nashville Predators player Fisher at one of her concerts in late 2008.More news: Oscars: Academy to add achievement in popular film category
The American Idol victor recently discussed the possibility of expanding her family in an interview with Redbook.
"I'm 35, so we may have missed our chance to have a big family", she told the magazine. "We always talk about adoption and doing it when our child or children are a little older". "In the meantime, we're lucky to be a part of organizations that help kids, because our focus right now in our lives is helping as many kids as possible".More news: Trump is losing the trade war, according to his favourite measure