Sex Ed

Eight Things Science Taught Us About Sex In 2018

December 26, 2018 by Justin Lehmiller


2018 has been memorable for a lot of reasons—including what science taught us about sex. Here’s a quick recap of some of the most interesting things we learned about sex this year.

1. The G-Spot probably isn’t what you think it is.

Scientists recently published one of the largest and most thorough anatomic explorations ever of the area commonly referred to as the G-Spot. The results turned up no evidence of a unique anatomic structure corresponding to the G-Spot, which suggests that perhaps rather than thinking of the G-Spot as a unique structure within the genital region, it may instead be better thought of as the area where the internal part of the clitoris, urethra, and vagina all happen to intersect. Read my write-up of this study here. (And, OK, technically this study was published in December 2017, but I didn’t see it in time to make last year’s list, so that’s why it’s on here!)

2. Women who have a better sense of smell have more orgasms.

A team of researchers based in Germany studied 70 healthy young adults about their sex lives and gave them a test of odor sensitivity. What they found was that people who were more sensitive to smells rated their sexual experiences as more pleasant. This was true for both men and women. Interestingly, they also found that women with a stronger sense of smell had more frequent orgasms during intercourse; however, there was no link between sense of smell and orgasms among men. What scientists think is happening here is that body odors are enhancing arousal among those with more sensitive noses (in other words, we’re talking about a pheromone-like effect). Read my write-up of this study here.

3. Speaking of orgasms…people’s orgasm faces look different across cultures.

Researchers showed participants from two different cultures (half Western and half East Asian) images of people with different facial expressions and asked them to indicate whether the emotion expressed was pain, orgasm, or something else. What they found was that the look of pain appeared to be universal, but the look of orgasm did not. The Western orgasm face included eyes that were opened wider and a mouth that was stretched vertically; the East Asian orgasm face included more smiling, with a raised brow and closed eyes. To learn more about this research, check out my write-up here.

4. Casual sex isn’t all that “casual.”

When researchers surveyed more than 600 college students about their willingness to engage in several different acts of intimacy and affection with a casual partner, they found that most participants seemed open to the idea of combining intimacy with casual sex. For instance, more than half of participants wanted to cuddle with a casual partner, and more than a quarter wanted to gaze into one another’s eyes. On average, women were more likely to want intimacy during casual sex than men; however, most men wanted intimacy, too. This tells us that casual sex is not necessarily an emotionless affair. Learn more about this research here.

5. Men and women have different counting strategies when asked about their number of previous sexual partners.

Several studies have found that men report having twice as many sex partners as women, a finding that has long puzzled sex researchers because it just doesn’t make mathematical sense. However, a study published over the summer yielded some important insight. It’s due, in part, to the fact that men tend to estimate their partners, while women are more likely to count them. Perhaps not surprisingly, men also tended to exaggerate how many partners they’d had.

6. Genital stimulation isn’t always necessary in order to reach orgasm.

People report that they can have orgasms from a variety of sensations and activities—and they don’t necessarily have to be sexual in nature. In a recent study, researchers documented all kinds of interesting ways people said they had reached orgasm, which included exercise (“horseback riding, biking, [and] ‘sitting and jumping on a Pilates ball’”), eating (from a “perfectly ripe cherry tomato” to tuna), and getting a tattoo or piercing. Read my write-up of this study here to learn more.

7. Your sexual fantasies say a lot about your personality.

I surveyed more than 4,000 people about their sexual fantasies and found that the content of people’s fantasies was very much a reflection of their unique personality traits. In particular, the Big Five traits of openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism were all linked to the kinds of fantasies people reported having. For instance, people who were more extraverted (i.e., outgoing) had more group sex and non-monogamy fantasies, while those who were more conscientious (i.e., detail oriented) focused more on the settings in which their fantasies took place. Learn more about this research here.

8. A lot of people occasionally report feeling tearfulness or sadness following sex.

Rather than feeling good, some people feel sad or irritable following what is otherwise a consensual and satisfying sexual encounter. When this occurs, it’s known as postcoital dysphoria—and new research shows that a lot of people experience it, regardless of gender. Nearly half of men and women surveyed report having experienced postcoital dysphoria before; however, fewer than 5% of men and women saying they experience it all or most of the time they have sex. Learn more about postcoital dysphoria in my write-up of this research here.

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Image Source: 123RF/ Carlo Toffolo

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Written by
Dr. Justin Lehmiller
Founder & Owner of Sex and Psychology

Dr. Justin Lehmiller is a social psychologist and Research Fellow at The Kinsey Institute. He runs the Sex and Psychology blog and podcast and is author of the popular book Tell Me What You Want. Dr. Lehmiller is an award-winning educator, and a prolific researcher who has published more than 50 academic works.

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