We Still Have No Idea Why Women Have Orgasms

Male orgasms are obvious. They serve to deliver sperm, which, if nature has its way, results in fertilizing an egg. The purpose of female orgasms, on the other hand, is less obvious. In fact, researchers still have no idea why they occur at all. Popular Science reports:

A new study has found no correlation between female orgasms and fertility. This undermines one popular hypothesis for why, evolutionarily, women have orgasms. Women may be more likely to conceive when they orgasm, according to the theory, thus passing on their ability to their offspring. But if frequent orgasmers don’t have any more kids than infrequent orgasmers, then it doesn’t matter. Sigh.

The study recruited around 8,500 women, including sisters and twins, and asked them all sorts of questions about their sex life, such as how often they reached orgasm.

The researchers found a weak correlation between how often women orgasmed and how many children they had, which seemed to suggest that the big O does matter, evolutionarily speaking. But! When the researchers looked at their data in more detail, they found that the correlation was weaker in identical twins than in non-identical sisters. If there were a genetic connection between orgasming and offspring number, you’d expect the correlation to be tighter with identical twins than with sisters who share less genetic material.

Nothing else the researchers tested, including possible outside factors like relationship length or how often a woman has sex, explained her frequency of orgasm.

Many researchers have tried their hand at understanding the purpose of female orgasms. Most hypothesize that the orgasms must have something to do with facilitating the meeting of sperm and egg, PopSci writes, though all have drawn a blank on actually finding evidence for this. Some women will likely be displeased to learn of an alternative hypothesis: that female orgasms, like male nipples, are nothing more than a non-functional byproduct of male orgasms—though many will also beg to differ on the “non-functional” bit.

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Rachel Nuwer | | READ MORE

Rachel Nuwer is a freelance science writer based in Brooklyn.