Mothers are 11.3 percent less likely to give birth on Halloween than they are on the days before and after the holiday.

Researchers from the Yale University School of Public Health found that induced births were down 18.7 percent and C-section births fell 16.9 percent on Halloween. This shouldn't be that surprising -- if given the choice, a parent might not want to have their child share a birthday with a darkly-themed holiday.

But here's where it gets really interesting. Natural births were also down 5.3 percent on Halloween. Becca Levy, who worked on the study, hypothesizes that a mother's desire to give or not give birth on a certain date "might affect a hormonal cascade, which could have an impact on the [birth's] timing."

The researchers also looked at Valentine's Day and found the opposite effect: births were up 5.3 percent on the love-themed holiday.

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