A new study finds that while men have more orgasms, when it comes to women, there are dramatic variations in orgasm rate depending on their sexual orientation.

An orgasm, for all the sparks and explosion, can be a complicated thing. Reaching orgasm happens more frequently for some than others. As it turns out, women have fewer, less predictable, and more varied orgasm experiences than men, according to a recent study published in the Journal of Sexual Medicine.

Researchers from the Kinsey Institute for Research in Sex, Gender, and Reproduction at Indiana University found that people of different genders and sexual orientations experience orgasm during sex with a familiar partner at different frequencies. While there are slight differences in orgasm rate for men across sexual orientation, for women the variation is more significant. Straight women are less likely to reach orgasm than lesbian women, and bisexual women experience orgasm the least frequently of all.

In a survey of 2,850 single men and women, women were found to experience orgasm with a familiar partner at an average rate of 63 percent, while men reached orgasm more than 85 percent of the time.

“Men and women experience different things and some are very intense and some are not. Some women claim to encounter different types of orgasms dependent on what is aroused and the type of genital stimulation,” said study co-author Justin Garcia, Ph.D., an assistant professor of gender studies at Indiana University and a researcher at the Kinsey Institute.

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The study found that heterosexual men and gay men both experience orgasm about 85 percent of the time. Heterosexual women reach orgasm at a rate of almost 62 percent, while for lesbian women, orgasm occurs nearly 75 percent of the time. Bisexual people reach orgasm at the lowest rate for each gender, at 58 percent for bisexual women and about 78 percent for bisexual men.

An orgasm, often considered the climax of sexual activity, can be a subjective experience, although there are physical responses associated in the moment. Orgasms can be characterized by intense sensation and pleasure, a discharge of erotic tension at sexual climax, and a temporarily altered state of consciousness, as well as psychophysiological responses like genital activity, involuntary pelvic musculature contractions, and changes in heart rate, the study says.

Just because the occurrence rate of orgasm among men and lesbian women is higher than among heterosexual and bisexual women doesn’t mean that the sex is more or less satisfying, Garcia explained. “Orgasm and satisfaction are two distinct constructs. There are a lot of overlaps between them, but they are distinct,” he said.

“It doesn’t mean it’s better, doesn’t mean it’s worse, it doesn’t mean it’s not satisfying,” he added. “Sex is a performance for everyone, and that’s a part of it.”

In the study, participants responded to an internet questionnaire. The study population was limited to those who have had sex within the past 12 months. Questions were asked broadly and focused on sex with a familiar partner, as there is already research showing that across genders and sexual orientations, there tend to be less orgasms in hookup situations.

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So why don’t women orgasm as frequently? There are several different arguments addressing the question. There is a possible evolutionary reason, as well as a biological reason dealing with the distance between the glans clitoris and urinary meatus. But the exact answer requires further study.

“We know that the classic argument is that for men, [orgasm] is so tied to ejaculation,” Garcia said. There is also the possibility that among lesbian women, there is better mutual attention paid to both partners and different sexual activities like cunnilingus. For heterosexual pairs, a tendency towards one type of sexual activity may reduce orgasm rate for the female partner.

“Among heterosexual couples it is often penetrative behavior over another type of activity,” he said. Familiarity, variation in sexual activity, and duration of sex may all contribute to a higher rate of orgasm for women.

“We know that there are all those different experiences, but there is very little research on the different types and what they mean,” Garcia said. “Those are questions for another day.” In an upcoming study looking at the sexual health of singles, Garcia and his team will address attitudes towards sexual experiences and the “first date.”

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