Chicago hospital celebrates baby boom after Cubs' World Series win

— -- Couples in Chicago had a great time celebrating the Cubs’ World Series championship run -- and the team has lots of tiny new fans to prove it.

A Chicago-area hospital said they are experiencing a baby boom about nine months after the Cubs' historic victory, which was 108 years in the making.

“You can definitely say it's been a little busy around the hospital,” Dr. Melissa Dennis, vice chairwoman of obstetrics and gynecology at Advocate Illinois Masonic Medical Center, told ABC News. “The number of births nearly doubled in the last few weeks, from an average of five births per day to nine.”

The medical team there celebrated on Wednesday by dressing newborns in the team's onesies and arranging a photo shoot with their families, the Cubs' trophy, and Clark, the team's mascot.

Natalie and Joe Pelnar, diehard fans and born-and-raised Chicagoans, were thrilled to welcome a little Cubby to their family. The Pelnars named their son Addison for Wrigley Field’s historic cross streets, Clark and Addison.

“We wanted to give him a name of something that would be around for a long time,” Joe Pelnar, 25, told ABC News. “Players come and go, but hopefully those street names will stay there forever.”

The proud new parents, who delivered Addison at a sister hospital, Advocate Good Shepherd Hospital in Barrington, Illinois, said they conceived him on the day the Cubs made it to the World Series by beating the Los Angeles Dodgers in Game 6.

“They made this one huge step and we said, ‘Let’s go for it,’” Natalie Pelnar, 24, said. “We had just gotten married, so we said, We’ll try this one time.’”

It turns out the Cubs were their lucky charm. The day after the Cubs took home the World Series championship, the Pelnars found out Natalie was pregnant.

“We had been celebrating with him the whole time and not knowing,” said Natalie Pelnar. “We didn’t know what to be happy for -- the World Series or us being pregnant. It was a huge moment for us.”

Another couple, Chris and Jenna Grooms, said they conceived their daughter, Rose, during the final week of the World Series.

“By that last winning night, I would have been pregnant, so Rose got to celebrate with us in that moment and we didn’t even know it,” Jenna Grooms, who gave birth a week late on July 25, said. “It was pretty incredible. Living in Chicago for that final game was awesome. As soon as they won, immediately outside horns were honking and people were driving down the street with radios and music playing. The energy was so incredible.”

The Grooms live a mile and a half away from Wrigley Field and said their daughter “doesn’t even have a choice” but to be a “Cubs fan forever.”

Dennis explained that while there has been an increase in the number of babies delivered, “it’s tough to definitively tie it back to the World Series win last fall.”

Nonetheless, “it's been fun to relive that amazing moment in history and celebrate these new babies and their Cubs-loving families,” she added. “With the hospital just a hop and a skip away from Wrigley Field, and as a Cubs fan myself, I'm used to seeing the Cubs spirit everywhere I go. But having these families here to celebrate their 'little sluggers' in such a special way is absolutely unforgettable."