Most popular day to be born? Sept 16.

North Americans would probably not be surprised to learn they do most of their cuddling in the winter months. And now a study has come along to prove it.

The Toronto Star reports that Amitabh Chandra, a professor of public policy at Harvard University, has examined the days when babies were born in the U.S. between 1973 and 1999 and determined the most popular day to be … September 16.

"Chandra's research looks at U.S. birthdays, not Canadian. But he says that it wouldn't be a stretch to hypothesize that the results might have similarities," reports the Star.

Lisa Weston, President of the Association of Ontario Midwives, agrees.

"I think it was last fall that we had such a busy time in our practice," she says. "And my partner called me and he said 'I just heard on the radio that this is the busiest time of year for people to have babies."

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"Because it lines up with holiday season," she continues. "So those babies that were conceived during the Decemeber/January holiday season are then being born in September and October. Whether planned or 'oopses,' that certainly makes sense in North America. That doesn't surprise me at all. "

The study also fits with Shine's story from a little under a year ago that listed the most popular birth months in Canada. The winner in the Shine story? August. This, of course, flew in the face of those who believed it would be the end of October (the products of extra-affectionate Valentine's Days).

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Chandra's study, which was mapped out visually in a heatmap on the Daily Viz, also showed that the least popular time to be born was December 23 through to December 26. And the least popular month to be born? January.

But contrary to the Star's suggestion that women might be scheduling Caesarean sections around Dec.25 to avoid giving birth on Christmas Day, Weston believes more natural forces might be at work.

"We see it all the time in midwifery that people will come into care and … they'll say, 'well, I don't want to have the baby on this day.' Because something happened on that day or it's somebody else's birthday," she explains. "Or we see a lot of women not giving birth on Christmas Day, especially when they have other kids. They keeping themselves from going into labour or the stress of the time will stop the hormones from doing what they need to do to start labour.

"I think that having specific thoughts about not wanting to go into labour until a specific time can release adrenaline in your system and adrenaline doesn't work very well with all your other hormones that we need to go into labour. "

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