The role of the female orgasm has been a head-scratcher for centuries. Case-in-point: Aristotle himself noted that the fact that human females don't need it to conceive clouded the quest for explanation.
The statistics that show it's an "uncommon" occurrence during heterosexual intercourse and the lack of correlation between orgasm and number of offspring deepen the mystery—which scientists at Yale and the Cincinnati Children's Hospital may have "solved," reports the Guardian.
Science reports there are about a dozen theories out there (read a few here); here's the upshot of this one, published in the Journal of Experimental Zoology: The human female orgasm is rooted in an ancestral kind of ovulation present in some mammals (cats, rabbits) today, in which sex triggers a surge of hormones which then triggers the egg's release.
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