Why Do Female Orgasms Exist?

Over the past few years, a lot of scientific light has been shone on the female orgasm. Unlike male orgasms, female orgasms are not necessary for the reproductive cycle; while male sperm is only provided via ejaculation, female orgasms seem to be an icing on the cake, a mechanism that exists solely to give pleasure instead of performing any vital function when it comes to furthering the species. A new study, though, claims that the female orgasm played a more necessary role in early human reproduction than we may think (at least theoretically).

Interestingly, the idea that the female orgasm is reproductively "inessential" hasn't held all the way through human history; in many European medieval medical texts, it's assumed that women's orgasms are just as necessary as male ones for a successful pregnancy, because pregnancy was thought to be a kind of "mingling" of seed from both women and men. Once we understood the fertilization process a little better, this view faded; but the medieval thinkers may have been onto something, at least in terms of early human history.

The study, published in August in the Journal of Experimental Zoology, raises a new theory about the origin of the female orgasm: that it's an evolutionary hangover, something left over from a time when female orgasms were actually a part of the reproductive process — and that we've gradually evolved in ways that separate orgasmic pleasure in women from successful impregnation. Basically, the theory alleges that once upon a time, we likely did need female orgasm to get pregnant.

But it's not an uncontroversial view. Let's get into the sticky business of the history of female orgasm, and what it might mean.

New Research Claims Female Orgasms May Have Induced Ovulation

In terms of human reproduction, the female orgasm's not a key part of the process any more. What really matters for conception is the reproductive cycle in women, which regulates their fertility, the release of eggs, and the other matters that combine with male sperm to make a healthy screaming baby after 9 months. But the researchers in the new study think this may not always have been the case.

They had a look at the history of mammals, from primitive to more modern ones, and noted something interesting: in many early mammals, ovulation in females was only triggered by the presence of males — either by males who were having sex with them, or just by males who were hanging around. In technical terms, it was ovulation that was "induced" by male mammals and what they did, rather than "spontaneous" ovulation, which is how humans work now; we ovulate every month whether there's a man around or not (often to our own annoyance and the general profit of the tampon industry).

Having induced ovulation actually makes a lot of sense; instead of wasting possible resources ovulating every month, you just ovulate when there's somebody around to potentially make babies with. But as mammals evolved, they tended to move from induced to spontaneous ovulation; and the researchers think we might have followed the same pattern.

But that's not the end of the story. The research also found that orgasm in women creates what one of the scientists, Mihaela Pavličev, called "an endocrine surge": a surge in hormones that, in other mammals, can spark off ovulation, even though it does nothing of the sort in humans. Once upon a time, a female orgasm might have triggered human ovulation, which is an amazing thought.

And the research didn't stop there; they looked at mammals who'd evolved from male-induced to spontaneous ovulation, and found that "evolution of spontaneous ovulation is correlated with increasing distance of clitoris from the copulatory canal." In other words, the move away from orgasm-induced ovulation to spontaneous ovulation was linked to clitorises getting harder to reach during sexual intercourse. As the orgasm became less essential to human reproduction, the clitoris moved further inside the body, out of the way of the "necessary" humping mechanisms.

A summary? The scientists think that we once needed female orgasms to trigger all the mechanisms for ovulating and having kids, and that they're still around as evolutionary leftovers, like the appendix.

But Female Orgasm Might Not Be So "Useless" After All

But this image of the female orgasm — doomed to irrelevance, hanging around because we haven't evolved out of it yet — hasn't convinced everyone in the scientific community; other scientists aren't yet sold that the data presented by the new study is legit, and there are a lot of other reasons that female orgasmic tendency might have hung around.

The purpose of female orgasm in modern sex has been debated for a long time, and there are a couple of decent theories about it. One is that it's a "sperm retention mechanism;" that is, the spasms of the orgasm might mean that it's easier for sperm to travel up into the reproductive tract, rather than flowing out.

Another theory suggests that it's to do with bonding between sexual partners. Female orgasm, according to this idea, creates a hormonal response that makes women bond to their sexual partners, ensuring a greater likelihood that both parents will stick around to raise any kids that ensue. (This theory might not hold a lot of water, though; a scientist thoroughly debunked the idea that oxytocin creates more bonding behavior in humans post-orgasm in 2011.)

And there's a third idea: that it evolved in order to help women choose good mates. Dr Kristen Mark outlines this theory for the Huffington Post: it says that "female orgasm has evolved to function in mate selection in order to better attract mates who will be invested long-term or to select higher quality sperm for higher quality offspring." Just because of the female orgasm might have been tied to ovulation at one point (and now isn't) doesn't mean it might not serve other purposes, too. It may well be a very multi-purpose pleasure mechanism.

The big issue with the new scientific idea about female orgasms is that it's largely hypothesis; the two scientists "concede that more data are needed to firm up their theory," Science reported, "though for now they have no plans to follow up themselves." (Other scientists also raised questions about whether the endocrine surge they reported was a real thing.) It appears that, for the moment, the history and the purpose of the female orgasm remain an open question. Because nothing evolves just for fun, alas.

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