“Whether women’s orgasm is an adaptation is arguably the most contentious question in the study of the evolution of human sexuality,” states a 2012 study. Indeed, the objective behind the existence of female orgasms has eluded scientists for ages — they know male orgasms aid reproduction by releasing sperms but cannot figure out why female orgasms exist. And so, different hypotheses to explain their presence have evolved over the years that have inspired lively, if not polarizing, debates.

Now, a new study attempts to add complexity to this discourse. Published in Evolutionary Psychology, the research looks at the evolutionary ropes behind orgasm and sexual desire among females — and how it may impact satisfaction in relationships. “The incredible variability in orgasm we see among females poses a very interesting evolutionary question,” co-author Patrick Nebl, an assistant professor of psychology at Elmhurst University in the U.S., said in a statement, adding that “there is still quite a bit of disagreement over whether it has an adaptive function and what that function might be.”

One camp argues that women orgasm in service of two adaptive functions. One, of mate selection — as a kind of a litmus test allowing women to assess the value of a long-term sexual partner. Two, of “pair-bonding,” courtesy of the oxytocin released during an orgasm, which aids emotional bonding between partners, ensuring committed, well-bonded parents are around to effectively nurture their offspring.

Another theory suggests that female orgasms — through the typical uterine contractions that are involved in it — help with sperm retention by causing the ejaculate to be “sucked in” better for fertilization. Then, there’s another hypothesis, which suggests female orgasms serve no purpose; they’re just an evolutionary accident — albeit a happy one, of course.

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In the present study, the researchers recruited 175 heterosexual, cis-gendered women with an average age of 19 for the study. Upon interviewing the participants, the study authors found a link between female orgasms and greater relationship satisfaction and duration.

It echoes the findings from a 2014 study which, too, support the “hypothesis that female orgasm evolved as a mate-selection tool for females and promotes long-term, pair-bonding.” The authors, there, had found that the intensity and frequency of female orgasms were related to their male “partner’s family income, his self-confidence, and how attractive he was… [in addition to] how many times they had sex per week, and ratings of sexual satisfaction.”

Interestingly, an explanation for the “orgasm gap” — the disparity in orgasms between cis-gendered men and women in heterosexual relationships — may be embedded in the mate-choice hypothesis. “[T]he failure of some women to orgasm regularly is not a dysfunction, but a sophisticated mate-selection strategy that evolved during prehistoric times,” a 2005 article in The Guardian states. “Women who fail to orgasm during sex may be genetically programmed to weed out unreliable men.”

However, is the present study conclusive proof of mate selection being the driving force behind female orgasms? And, does it automatically dismiss other hypotheses? Nebl doesn’t think so. “I certainly don’t think this study ‘proves’ anything, rather it helps add evidence that orgasm might function as a mate-selection tool that promotes pair bonding,” he noted.

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Nebl believes the study serves yet another purpose — beyond ascertaining the objective behind female orgasms. “Orgasm is highly variable between females, and many females struggle with difficulty or inability to achieve orgasm. Struggling with sexual satisfaction affects relationship satisfaction — and overall satisfaction — and can be distressing, even leading to self-blame… The knowledge that variability in female orgasm may be by evolutionary design, rather than being evidence of dysfunction, may provide some solace to women struggling with their sexual satisfaction,” he explained.

Indeed, even though female orgasms may still be shrouded in layers of mystery, it’s reassuring to learn that not orgasming may serve a greater purpose. In the meantime, future research can, perhaps, include more than just heterosexual women to derive their conclusions from a more diverse set of responses.

Deep dives into evolutionary theories aside, one can hope the present study doesn’t discourage women in heterosexual relationships from pursuing greater sexual satisfaction — especially given the existing orgasm gap, and to add to that, past research suggesting that infrequent orgasms lower people’s expectations of, and even desire for, orgasming. The “pursuit of pleasure,” as Samatha from Sex And The City would perhaps call it, must continue.