This Week in Sex is a weekly summary of news and research related to sexual behavior, sexuality education, contraception, STIs, and more.

When Men “Fake It,” Their Motives Are Often Altruistic 

In the pilot episode of the TV show Masters of Sex, Dr. William Masters seems shocked to learn that women might fake orgasms. When he asks his new assistant, Virginia Johnson (who becomes his research partner and later his wife), why women might do such a thing, she replies: “To get a man to climax quickly. Usually so the woman can get back to whatever it is she’d rather be doing.”

Masters and Johnson, whose real-life work and relationship was fictionalized in that Showtime series, were pioneers of sex research in the 1950s and 1960s. Those who follow in their footsteps today are still trying to answer some of the same questions.

A new study from two Canadian researchers looks not at why women fake orgasms, but why men do—and what, if any, correlation there is between faking it and relationship satisfaction.

Researchers surveyed 230 young men between ages 18 and 29 who had admitted to faking an orgasm at least once in their current relationship. Using an online survey, they asked these men at what point in their relationship they began to fake orgasms, how often they did so, and why. They also measured sexual desire and relationship satisfaction.

On average, the men began faking orgasms 14 months into the relationship. On average, the men said they faked an orgasm in about 30 percent of their sexual encounters; 71 percent of participants reported having faked an orgasm during penile-vaginal intercourse; 27 percent during oral sex; 22 percent during anal intercourse; 18 percent during manual stimulation by a partner; and 5 percent while being stimulated with a sex toy by a partner.

Many of the reasons the men gave for faking orgasm revolved around making their partners feel better—including giving their partner an ego boost, feigning simultaneous orgasms, or avoiding upsetting their partner.

Interestingly, men who faked it for these relationship reasons tended to report higher levels of sexual desire. The authors theorize, “It is possible that men feel good when giving a partner pleasure, either out of love and generosity, or because it provides indirect reassurance of their own sexual adequacy, leading them to associate this reward with sexual activity, further leading them to seek more sex (i.e., experience higher levels of sexual desire).”

Men who faked orgasms also had higher levels of relationship satisfaction, though the authors point out that pretending might not lead to relationship satisfaction; those who are already satisfied may be more likely to fake orgasms for the sake of their partner’s feelings.

While it’s reassuring to know that some men fake orgasms for altruistic reasons, we here at This Week in Sex are not big fans of the fake orgasm, regardless of the gender or the reason. Once in a while is understandable “to get back to whatever it is [you’d] rather be doing,” as Johnson said. But, for the most part, we think it’s better to talk to partners about why you didn’t have a real one this time and what could be different next time.

Is Frequent Ejaculation a Cancer Prevention Method? 

Another new study found that men who ejaculated more frequently were less likely to be diagnosed with prostate cancer. Researchers followed about 32,000 men for almost 20 years, using the national Health Professionals Follow-up Study  at the Harvard School of Public Health. The men were all in their 20s when the study started in 1992 and therefore their 40s (or close to it) when it ended in 2010. They filled out questionnaires that asked about their sexual behavior (including masturbation), and researchers also looked at the men’s medical records.

During the course of the study, about 4,000 of the men were diagnosed with prostate cancer. The researchers’ analysis showed that men who ejaculated at least 21 times a month in their 20s were 19 percent less likely to be diagnosed with prostate cancer than men who ejaculated no more than seven times a month at that age. Similarly, men who ejaculated more often in their 40s were 22 percent less likely to be diagnosed with prostate cancer diagnosis.

There are some limitations of the study, including the possible inaccuracy of self-reported data on ejaculation and the lack of diversity among participants. In addition, one urologist who spoke to Reuters questioned the fact that the relationship between ejaculation and prostate cancer applied mostly to less invasive forms of the disease. Dr. Behfar Ehdaie of the Memorial Sloan Kettering Cancer Center in New York, who was not part of the study, noted: “If ejaculation frequency was truly a causal factor for prostate cancer development, we would expect to find the association across all prostate cancer risk categories.”

And, of course, correlation does not equal causation. There could be other reasons that men who ejaculate less often are more likely to get prostate cancer. Specifically, as study co-author Dr. Jennifer Rider points out, men who ejaculate less than three times a month may be suffering from other health issues.

Still, there could be a prevention strategy in the findings. Rider told Reuters in an email: “The results of our study suggest that ejaculation and safe sexual activity throughout adulthood could be a beneficial strategy for reducing the risk of prostate cancer.”

Given that ejaculation tends to be enjoyable, it seems like a pretty good idea to try even while more research into the correlation is being conducted.

Emerging Options for Women With Sexual Arousal Issues

When the drug Addyi was under development, people referred to it as “female Viagra” because it was intended to address women’s sexual dysfunction. But the two treatments actually work very differently. While Viagra causes an erection by increasing blood flow to the penis, Addyi (or flibanserin) works on chemicals in the brain to increase sexual desire.

Now, researchers are developing a new treatment for women that is actually much more similar to Viagra. A company called Creative Medical Technologies filed a patent last week for a treatment that uses regenerative stem cells to increase blood flow to the vagina. Unlike Addyi, this treatment is designed for women who desire sex but are having trouble becoming aroused. Increasing blood flow to the vagina can cause the clitoris to become erect and the vagina to lubricate, both of which are important parts of the arousal stage of sexual response.

The treatment still needs more research and, of course, FDA approval, which was a very controversial process for Addyi’s maker. Moreover, it’s not clear how big the market is for female sexual dysfunction treatment, as prescriptions for Addyi have been low since its market release last October.