(NEW YORK) -- It's a day that arrives once in a century: 11/11/11.
Our fascination with this and other numerical patterns is no mystery, according to one anthropology professor. It's a by-product of human evolution. Our senses are "geared toward pattern recognition," John Hoopes, an associate professor of anthropology at the University of Kansas, told ABC News, "because it gives us an advantage for survival."
Getting Married on 11/11/11
Brides magazine estimates more than 46,000 weddings will take place Friday, which is 10 times more than a typical Friday in November.
Brides adhere to a lot of superstitions, such as the old adages that suggest wearing something borrowed or blue, says Jackie Lebowitz, assistant managing editor of the magazine. And then there's the dictum that you shouldn't let your husband-to-be see you wearing your wedding gown.
It doesn't hurt that 11/11/11, is an especially memorable number for anniversaries.
"With 11, you have the significance of the number one -- two becoming one, the 'number one marriage,' one soul mate, finding 'the one,'" said Lebowitz, not to mention that it's a "once in a lifetime" experience.
Expectant mothers in South Korea have "inundated" hospitals requesting that their cesarean section delivery happen Friday, according to reports.
The number of appointments for c-section births was 20 percent higher than in previous years because South Koreans want their children to have a Korean resident registration number that begins with "111111."
In the United States, the demand for c-sections doesn't appear to be as great. But one Des Moines obstetrician said he's offering expectant mothers refunds on all his delivery fees if they give birth on the unusual date.
The money will be funneled into "a special account for the baby, to be given to the baby in the lump sum amount when they turn 21," the doctor said.
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