Ask Dr. Justin Lehmiller

Coral contributor, Kinsey Institute Research Fellow and internationally-recognized sex educator answers some user-submitted questions.

Some women find that certain sexual positions allow them to reach orgasm faster and/or more consistently. Part of the reason for this is because some positions offer more clitoral stimulation than others.

Studies have repeatedly found that women are much more likely to reach orgasm to the extent that clitoral stimulation occurs during intercourse. This can be accomplished through the use of one’s own (or a partner’s) hands, sex toys, or body positioning.

When a woman is on top of a male partner during vaginal intercourse and facing him, often referred to as the “cowgirl” position, she is able to grind or rub her clitoris against her partner’s body the entire time, which is why many women find that they’re more likely to have an orgasm in this position.

By contrast, in the missionary style man-on-top position, the clitoris may get very little in the way of direct stimulation, especially for a woman whose clitoris happens to sit further from her vaginal opening. Clitoral-vaginal distance actually varies quite a bit from woman to woman, and women with a greater distance often find that switching up positions and/or adding more manual clitoral stimulation is essential for orgasm during intercourse.


Do you watch porn with your partner? How does this affect your sexual relationship?

Some porn-watchers only engage in this behavior alone, others do it with their partners, and yet others do a bit of both. What we see in the research is that people who report watching porn with their partners tend to be more sexually satisfied.

This makes sense because porn, after all, is a powerful form of sexual novelty. People tend to grow bored of sexual routines easily and need to keep mixing things up in the bedroom in order to maintain excitement and keep passion alive in their relationships. Porn is a simple and easy way of getting that novelty fix.

That said, couples who watch porn together tend to be trying other new things together as well. So it’s not just that they’re watching porn, they also tend to be exploring other sexual novelties, such as using sex toys, role-playing, going on date nights, and so forth.

When considered in this context, as one of many forms of shared sexual novelty among partners, porn use tends to have a positive impact on relationships.


So I’m a male in my mid 30s. I was interested in the penis extenders/traction devices that stretch the penis to a bigger size. Supposedly it was made to correct Peronies disease in men. I’m average size with a normal shape (6 inches long and 5.5 inches girth) but my own body image issues and society’s expectations on men make me want to try this out. Do these devices work?  What are the risks and benefits? What kind of results could I get? This isn’t about my sexual performance but more about my body image.

First, based on the measurements you provided, you’re actually above average in terms of penis size. In a study of over 15,000 penises, researchers put the average length at 5.2 inches and the average girth at 4.6 inches. People have a tendency to think that the average penis is quite a bit larger than it actually is, in part, due to the fact that porn penises tend to be so disproportionately large.

So it’s important to step back and correct this misperception. Far too many men feel inadequate and have poor body image despite having average to above-average genitals. It’s important to learn to love your body the way it is and stop making unhelpful comparisons to porn stars. Your penis is normal and there’s nothing wrong with it.

I know changing the way you see yourself is easier said than done, but if you find your penis size to be very distressing to the point where it’s becoming a preoccupation and it’s interfering with your sex and social life, it’s important to speak to a therapist. Some men have penile dysmorphia, in which they’re convinced that they have a major flaw or defect in their penis that isn’t noticed by or considered a problem by others. Some of these men end up going to extreme lengths to change their penis size, including undergoing very risky and expensive procedures that end up causing more problems than they solve.

That said, regarding your question about extenders, there’s very limited research looking at their effects, but a few small studies (see here and here) have found that usage increased length (but not girth) by about 0.7-0.9 inches.

However, these were super small studies and it’s not clear how typical these results are. Also, usage of these devices requires extreme dedication. Instructions advise wearing them for several hours per day every day for several months. Some find these devices uncomfortable to wear, and if used improperly, they can potentially damage penile tissue.

Thus, at best, there’s potential for a small gain, but that has to be balanced against the time commitment and risks.

The truth is that there’s very little you can do to safely change penis size in any kind of significant way in adulthood, which is another reason why it’s important to learn to love your body just the way it is.