Pietrangelo shared the news via Instagram on Saturday. It included a picture of him holding the three children in what appears to be the delivery room.
"Welcome to the world Evelyn, Oliver, Theodore," he wrote. "It's already been an amazing 24 hours."
The Blues tweeted the photo and congratulated their 28-year-old captain.
Pietrangelo, the No. 4 pick by the Blues in the 2008 NHL Draft, married Jayne, who is from St. Louis, in 2016.