Category Archives: Sex Science

Contraception influences sexual desire in committed relationships

The role of human sex outside of reproduction remains something of an evolutionary mystery. But scientists believe that it is partly about tying the parties in the relationship together.

By Liv Ragnhild Sjursen

How often women in heterosexual couples desire sex depends on how committed the relationship is and what type of birth control the woman uses.

Sex is quite wonderful when the goal is to have children. But sex can also serve as a “glue” in a committed relationship.

Most animals have periods when they come into heat, and outside of these periods they don’t find sex interesting at all.

Humans, however, are constantly interested in sex. This interest can seem like a waste of energy, but an evolutionary perspective may explain why we function this way.

More sex with progesterone and commitment

A new study from NTNU and the University of New Mexico confirm that sex is important for pair–bonding between men and women in relationships.

The researchers also found a correlation between the type of oral contraceptive women use and how often couples have sex.

The findings were recently published in the scientific journal Evolution & Human Behavior.

“The function of sex in humans outside ovulation is an evolutionary mystery. But we believe that it has to do with binding the parties in the relationship together,” says Leif Edward Ottesen Kennair, a professor of psychology at NTNU.

Kennair worked with Trond Viggo Grøntvedt, Nick Grebe and University of New Mexico Professor Steve Gangestad to ask hundreds of Norwegian heterosexual women about contraception, sex and relationships.

Their results show that of women in long-term relationships and who are using hormonal contraception, those who are more committed to their relationships have more sex with partners, as one might expect.

“But this association was especially true when the contraceptive that women used had potent levels of synthetic hormones that mimic the effects of the natural hormone progesterone, and lower levels of the hormone oestrogen,” Gangestad said.

“We’re talking about intercourse here, not other types of sex like oral sex, masturbation and such. This strengthens the idea that sex outside the ovulation phase has a function besides just pleasure,” says Grøntvedt.

Big differences between types of contraceptives

Hormonal contraceptives, like birth control pills, implantable rods and patches, contain two types of hormones:

Oestrogen, which naturally peaks just before ovulation when naturally cycling women can conceive offspring, and hormones that have the same effect as progesterone, which naturally peaks during the extended sexual phase, a time when offspring cannot be conceived.

The levels of each hormone type vary in different contraceptives. Hence, some contraceptives mimic hormones that are more characteristic of ovulation, whereas others mimic hormones when women can’t conceive.

The women who used contraception with more oestrogen were most sexually active when they were in a less committed relationship.

On the other hand, women who used contraception with more progesterone were the most sexually active when they were faithful and loyal to their partners.

“Before we did this study, we didn’t know how much difference there was between the two types of hormonal contraceptives,” says Grøntvedt.

A credible holistic picture

The researchers surveyed two groups of women. All the women were using hormonal contraception and were in committed, heterosexual relationships.

One group consisted of 112 women that researchers followed over a 12-week period. The women were asked how often and when in their cycle they had sex.

The second sample group consisted of 275 women in long–term relationships who used hormonal contraception.

This group was not followed over time, but the researchers asked them how many times they had had sex in the past week. This type of study – using data collected at a specific point in time – is called a cross-sectional study.

Both groups were asked to indicate the type of contraception they were using, and if a pill, which brand it was.

“Since we examined these two groups using different methods – a snapshot for the one group and a longitudinal study for the other – we can be confident that the results provide a reliable overall picture,” Grøntvedt said.

Natural or synthetic hormones had similar effects

The basis for the NTNU study was a 2013 American study, where 50 women and their partners answered a series of questions about their relationships, menstrual cycles and frequency of sex.

None of these women were using any kind of hormonal contraception, so only their natural hormones were involved.

The study showed that women initiated sex more in the extended sexual phase – when they were not ovulating and progesterone was the dominant hormone – if they were invested in the relationship.

NTNU researchers wanted to verify the American results in their study, but with participants who were using a hormonal contraceptive that simulates a natural cycle.

Their results were the same as in the US study, in which women were not using any hormonal birth control.

The researchers were thus able to show that how often women have sex is linked to how committed they feel towards their partner and the type of hormone they are governed by, whether natural or synthetic.

“A lot of social psychology studies that have led to cool discoveries through the ages have lost status, because it hasn’t been possible to copy them and verify the results.”

“We are extremely pleased to have been able to verify the results of the study by Grebe and his colleagues, and we are equally pleased that we have also made new discoveries,” Kennair says.

Complete Article HERE!

Lacking the desire to have sex with your partner?

Scientists think they know how to cure your problem – and it’s all down to chocolate

Scientists found kisspeptin, which is found in chocolate, helps to make men much more interested in sex and relationships

By Victoria Allen

A ‘chocolate hormone’ could help to get couples in the mood for sex and fall more deeply in love.

Kisspeptin, which is named after a chocolate snack, is the hormone in the brain which kickstarts puberty.

And it may explain something about the behaviour of teenage boys, after scientists found it makes men much more interested in sex and relationships.

Young men injected with the hormone and then given brain scans showed a flurry of activity in the parts of the brain activated by sexual arousal and romance. It means similar injections could be used to help men to start a family.

Professor Waljit Dhillo, the lead author of the research from Imperial College London, said: ‘Our initial findings are novel and exciting as they indicate that kisspeptin plays a role in stimulating some of the emotions and responses that lead to sex and reproduction.

‘Ultimately, we are keen to look into whether kisspeptin could be an effective treatment for psychosexual disorders, and potentially help countless couples who struggle to conceive.’

One in 10 men in the UK are believed to have sexual problems, many suffering a lack of libido caused by relationship issues, stress and anxiety.

This can cause problems for couples trying for a child and advised to have regular sex throughout the month.

But kisspeptin is hoped to hold the answer, following a trial involving 29 healthy young men.

Those injected with kisspeptin, discovered in the mid-1990s in Hershey, Pennsylvania, and named after sweets from the city called Hershey’s Chocolate Kisses, reacted differently to sexual and non-sexual romantic pictures of couples.

In an MRI scanner, where their brains were monitored, there was greater activity in the parts of the brain typically activated by sexual arousal and romance than the men given a placebo.

Professor Dhillo said: ‘Most of the research and treatment methods for infertility to date have focused on the biological factors that may make it difficult for a couple to conceive naturally.

‘These of course play a huge part in reproduction, but the role that the brain and emotional processing play in this process is also very important, and only partially understood.’

The effect is likely to come from kisspeptin’s role in starting puberty, by stimulating the release of reproductive hormones.

A study from Edinburgh University previously found it fuels the production of testosterone, which is key to male libido and fertility

The researchers now want to study how the hormone affects women as well as men, while kisspeptin might also work as an antidepressant.

Volunteers shown negative and fearful emotional faces in pictures said they felt less bad in follow-up questionnaires after receiving the hormone, with less activity in brain structures important in regulating a bad mood.

Dr Alexander Comninos, first author of the study at Imperial, said: ‘Our study shows that kisspeptin boosts sexual and romantic brain activity as well as decreasing negative mood.

‘This raises the interesting possibility that kisspeptin may have uses in treating psychosexual disorders and depression which are major health problems which often occur together, but further studies would be needed to investigate this.’

Complete Article HERE!

10 Things Scientists Discovered About Sex This Year

By Justin Lehmiller

This year has been memorable for a lot of reasons, but one that may not be immediately obvious is that we learned a lot about the science of sex in 2016. Among other things, sex researchers brought us one step closer to a male version of the birth control pill, they debunked the idea that porn kills love, and they discovered that having a cat just might make you more inclined toward kinky sex (yep, you read that right). Let’s take a closer look at these findings and some of the other fascinating things scientists taught us about sex in 2016.

Americans are warming up to the idea of open relationships.

Americans are more interested than ever in consensual non-monogamy (CNM), or the practice of having multiple sexual and/or romantic relationships at the same time. A study published in The Journal of Sex Research in May found that Google searches for two forms of CNM—open relationships and polyamory—have significantly increased across the past decade. At the same time, a study published in the Journal of Sex & Marital Therapy found that more people are practicing CNM than previously thought: in a nationally representative survey of single Americans, more than 1 in 5 said they had been in a sexually open relationship before. Table for more than two, please.

We’re getting closer to a male version of the birth control pill.

An October study from The Journal of Clinical Endocrinology & Metabolism reported the results of a clinical trial in which men were given hormone injections designed to suppress their sperm production. The results were stunning: over the course of a year, the pregnancy rate for couples taking part in the study was just 1.57 out of 100. Unfortunately, however, the rate of side effects was very high, which led an external review board to recommend shutting down the study. Although this injection won’t be hitting the market, this study provides optimism that we’re not too far off from having a male equivalent of the female birth control pill.

Millennials are identifying as LGB at much higher rates than Gen Xers.

In January, the CDC released a report revealing major generational differences in Americans’ sexual identities. Specifically, millennials aged 18-24 were almost twice as likely to identify as gay, lesbian, or bisexual than Gen Xers aged 35-44. Millennials were more likely to report having engaged in same-sex behavior, too. However, whether this means same-sex attraction is actually increasing or if it’s just a sign that younger folks are more comfortable acknowledging their non-heterosexuality, we can’t say for sure.

The HPV vaccine has been wildly effective at reducing cancer.

In August, scientists reported that, in the ten years since the first vaccine for the human papilloma virus (HPV) was administered, rates of cervical cancer have been halved. If we can increase vaccination rates even further, there’s a chance that HPV-related cancers—including those of the cervix, anus, throat, and penis—could be eradicated within just a few decades.

Porn doesn’t change how men feel about their relationships.

A classic study from the 1980s found that heterosexual married men reported less love for their wives after viewing images of sexy magazine centerfolds compared to images of abstract art. This year, researchers tried three times to replicate the effect, but found nothing. Nada. Zip. Zero. These findings suggest that porn probably doesn’t kill love after all.

BDSM acts can produce an altered state of consciousness.

In May, a study published in the journal PLOS ONE looked at the psychological experiences of people who took part in an extreme masochistic ritual in which their skin was pierced with hooks that had weights attached. These participants demonstrated evidence of an altered mental state known as transient hypofrontality, described as “reductions in pain, living in the here and now, little active decision making, little active logic, and feelings of floating and peacefulness.” This suggests that BDSM acts have the potential to be a very spiritual experience.

We might be able to treat low sexual desire by electrically stimulating the brain.

In a November study published in the journal PLOS ONE, researchers found that delivering electrical stimulation to the brain changes the way we respond to sexual stimulation. Specifically, a targeted cranial “zap” appears to enhance the response that occurs in the brain’s pleasure centers. This suggests that we might actually be able to use brain stimulation as a treatment for people who complain of low sexual desire in the not too distant future.

Sexual arousal puts us in a risk-taking state of mind.

A January study published in the Archives of Sexual Behavior reveals that being horny can make us susceptible to taking risks, including those that are both sexual and non-sexual. In one study, participants who watched an X-rated film subsequently expressed more willingness to keep having sex after noticing a broken condom. In another study, sexually aroused participants made riskier moves in a game of computerized blackjack. These findings suggest that, when we’re feeling hot and bothered, well, we can’t be bothered to properly evaluate risks.

Women can detect when other women are ovulating, an ability they might use to protect their relationships.

In an April study published in the Journal of Personality and Social Psychology, researchers showed female participants photos of a woman who was either ovulating or not. Those who saw an ovulating woman were the most worried about keeping their partners away from her, but this was only true for participants with attractive partners. This suggests that women may have evolved the ability to pick up on other women’s ovulation status as a means of helping them to guard desirable mates from potential relationship threats.

Having a cat might increase your interest in kinky sex.

A July study published in the journal Evolutionary Psychology reported that people’s attraction to kinky sex depended upon whether they had been infected with toxoplasmosis, a parasitic disease that can be passed from cats to humans. Specifically, those who said they had been infected were more into bondage, violence, zoophilia, and fetishism. Why is that? The researchers suspect that it’s because this infection affects the circuits of the brain involved in fear, given that in mice and rats, toxoplasmosis switches their natural fear of cat smell into an attraction toward it.

Here’s to hoping 2017 is another mind-blowing year for sex research!

Complete Article HERE!

Lack Of Penis Bone In Humans Linked To Monogamous Relationships, Quick Sex

Scientists reveal why humans do not have a penis bone.

By

Many of us call erections “boners,” although there’s no actual bone in the penis. This bone has been the subject of many debates as several animals have them in diverse sizes and lengths, but humans don’t. Evolutionary scientists at the University College London suggest this strange anomaly is a consequence of monogamy and quick sex.

The penis bone, also known as the “baculum,” evolved in mammals more than 95 million years ago, and was spotted in the first primates that emerged about 50 million years ago, according to the researchers. The baculum became larger in some animals and smaller in others. For example, in the walrus, it can be two feet long, while in a monkey it’s about the length of a human fingernail.

Previous research has found the penis bone increases the potential duration of intercourse, and the frequency with which sex can take place. A lioness can copulate 100 times per day, sometimes with only four-minute intervals, but has just a 38 percent conception rate. This means males need to have better sexual stamina to achieve the best chance of paternity.

So, why do humans lack a penis bone?

The recent study, published in Proceedings of the Royal Society, found a link between penis bone length, promiscuity, and sex duration. Some species have longer penis bones because they engage in “prolonged intromission,” which means the act of penetration lasts for more than three minutes. Longer intromission times are more common among polygamous mating species, where multiple males mate with multiple females, like bonobos and chimps. This mating system creates an intense competition for fertilization, and reduces a female’s access to more mates by having males spend more time having sex with them, according to the study.

The penis bone is attached at the tip of the penis rather than the base to provide structural support for animals who do prolonged intromission, and to keep the urethra open.

The researchers believe humans lost their penis bones when monogamy became a dominant reproductive strategy about 1.9 million years ago.

“We think that is when the human baculum would have disappeared because the mating system changed at that point,” Kit Opie, a co-author of the study at University College London, told The Guardian.

Opie and his colleague Miranda Brindle believe the male does not need to spend a long time penetrating the female since she is not likely to be leapt by other amorous males. Therefore, the reduction of competition for mates means humans are less likely to need a penis bone. Opie adds, despite popular belief, humans do not generally need longer than three minutes to get the job done, and successfully impregnate a woman.

“We are actually one of the species that comes in below the three minute cut-off where these things come in handy,” he said.

Scientists have just begun to put together the function of this mysterious bone. They do agree changes in the penis bone are driven as part of a mating strategy. This means a bigger penis bone is better when it comes to sexual competition.

Human males, do not feel bad — if the penis bone is damaged, it could take as long as other broken bones to heal.

Complete Article HERE!

Can kinky sex make you more creative?

Researchers claim BDSM can help people achieve ‘altered states of consciousness’

By Cheyenne Macdonald

Engaging in kinky sex may send you into an altered state of consciousness and even unlock your inner creativity, according to a new study. The research also suggests BDSM reduces psychological stress, improves moods, and increases sexual arousal.

Engaging in kinky sex may send you into an altered state of consciousness and even unlock your inner creativity, according to a new study.

Using a small sample of participants from the kink-focused social network Fetlife, researchers investigated the mind-altering effects of BDSM – bondage/discipline, dominance/submission, and sadism/masochism.

Not only were these activities found to produce two types of altered states, but research suggests BDSM also reduces psychological stress, improves moods, and increases sexual arousal.

While previous studies have attempted to investigate this phenomena, no other research has actually put it to the test, the researchers explain in a paper published to the journal Psychology of Consciousness: Theory, Research, and Practice.

So, researchers from the Science of BDSM Research Team at Northern Illinois University recruited seven pairs of self-identified ‘switches’ – people who were willing to be randomly assigned to either a top or bottom role in a BDSM scene.

This way, the researchers explain, the differences observed in the study could be better attributed to the role rather than the individual.

Fourteen people participated in total, with 10 women and four men between the ages of 23 and 64.

For the experiments, the participants partook in seven scenes which involved everything from gentle touching and communication to striking, bondage, and fetish dress.

Each of the participants provided five saliva samples throughout the experiments, and were asked to complete three Stroop tests, involving words and colours: one prior to their assignment, one before the scene, and one after it had ended.

The test measured for an altered state of consciousness aligned with Dietrich’s transient hypofrontality, which relates to daydreaming, runner’s high, meditation, and even some drug highs.

Along with this, the participants were also given a measure of mental ‘flow’ following each scene, using the Flow State Scale ranging from ‘strongly disagree’ to ‘strongly agree.’

Flow is a nine-dimensional altered state conceptualized by Csikszentmihalyi, and is achieved during ‘optimal experiences,’ the researchers explain.

The dimensions of flow include ‘challenge-skill balance, action-awareness merging, clear goals, unambiguous feedback, concentration on task, sense of control, loss of self-consciousness, time transformation,’ and feelings of intrinsic reward.

The experiments revealed that the bottom role and the top role in BDSM are each associated with a distinct altered state of consciousness, both of which have previously been tied to creativity.

According to the researchers, ‘topping’ is linked to the state which aligned with Csikszentmihalyi’s flow, while ‘bottoming’ is associated with both Dietrich’s transient hypofrontality and some aspects of flow.

The team says these activities also reduced stress and negative affect in the participants, and increased sexual arousal.

While BDSM has long been a stigmatized practice, the authors say the finding support the idea that there are numerous factors driving these preferences that do not relate to mental disorder.

‘The results contribute to a growing body of evidence that individuals pursue BDSM for nonpathological reasons,’ the researchers conclude, ‘including the pleasant altered states of consciousness these activities are theorized to produce.’

Complete Article HERE!