The Bachelor couple named their first child together Samuel Thomas Lowe, who was born on Saturday.
"God is good! We had a healthy baby boy named Samuel Thomas. Thank you everyone for your prayers and support!" Lowe, 32, tweeted.
Giudici, 30, also took to Twitter to confirm their baby boy's arrival, tweeting, "I'm in love with another boy, my son Samuel Thomas Lowe."
A source toldUs Weekly that the new parents are "so in love" with Samuel already.
"[They] are excited to be a family of three," the source said. "Catherine and the baby are doing great. They're both healthy and happy."
Lowe also couldn't be more ecstatic that he gets to raise a boy. He revealed right after Giudici announced her pregnancy in December 2015 that he was secretly rooting for a son.
"He wants to teach him sports and things like that but he also is really excited to raise a great gentleman," the source told the magazine. "He is so close with his dad and feels so lucky to have a great dad as a role model and wants to be that for his son."
Lowe and Giudici, who got engaged on The Bachelor's seventeenth season and then wed in a live ABC television special in January 2014, told E! News in May that Giudici's mother and sister will stay with them for about a month to help out with the newborn.
"I know to most husbands that might sound daunting, but we love them and we're excited about it," Lowe said at the time, adding that family members also live close by to their home in Dallas, TX. "If we need to drop off the baby so they can babysit, it won't be a problem."
The couple reportedly relaxed on an April babymoon in Palm Springs, CA, and celebrated their baby's upcoming birth with a flamingo-themed baby shower in May.