— -- Every time a snowstorm keeps people indoors, there's someone around to make a joke about more babies being born nine months later.
But experts are divided over whether blizzard baby booms are real.
"Absolutely," said Dr. Laura Corio, an OB/GYN at Mount Sinai Hospital in New York City. "When we had [Hurricane] Irene, nine months later, I was so busy."
She said she's sure that there were also Superstorm Sandy babies who were born nine months after the October 2013 storm that crippled New York and New Jersey for days.
"I don't think it's a myth. I really don't," she said. "I think these things do happen if you look back."
ABC News reported in 2013 that hospitals in Manhattan, including St. Luke's-Roosevelt Hospital, saw a 10 percent to 20 percent uptick in births following the fall 2012 superstorm, but others, like Mt. Sinai Hospital, said there was no such thing as a Sandy baby boom.
Dr. Marjorie Greenfield, chief of obstetrics and gynecology at University Hospitals Case Medical Center in Cleveland, Ohio, said baby booms tied to big storms and power outages have been disproved in the medical literature.
"It's kind of fun to speculate and to imagine that people are bored and they make like bunnies," Greenfield said. "But the thing is, a lot of these things are reporting bias."
By that, she means researchers see a spike in births and go back nine months to try to find the cause. But there are certainly storms and events where there are no birth spikes nine months later, she said.
Dr. Jennifer Ashton, a senior medical contributor for ABC News and practicing OB/GYN, agreed there's "no medical basis" for the blizzard baby myth. Birth rates vary naturally, Greenfield said.
Still, researchers at the University of Texas at Austin and Johns Hopkins University studied birth rates following hurricanes in 2007 and concluded that low severity storm warnings had a "positive and significant" effect on fertility, and high severity warnings had a negative effect.