ResearchBlogging.orgYes another sex article (what can I say other than they’re fascinating and entertaining to read at the same time) but maybe not as risque as vibrator use.  PhD student Rui Miguel Costa and Professor Stuart Brody surveyed 30 Portuguese women (mean age 25.8, SD 5.33) to find out whether frequency of different sexual behaviors and corresponding orgasm rates could be linked with relationship quality.  The article, published in the Journal of Sex & Marital Therapy, (of course behind a subscription pay-wall, sorry guys) came out with some interesting conclusions, like penile-vaginal intercourse orgasm and frequency was positively correlated with quality measures while masturbation was negatively correlated to love.

The women surveyed responded to questions about sexual behavior as well as a six component quality survey, the Perceived Relationship Quality Components Inventory (PRQC).  This survey measured satisfaction, commitment, intimacy, trust, passion, and love on a 7-point scale.  Let’s check out some data.

Correlation between sexual behavior and relationship quality

Masturbation was only significantly correlated with one measure on the study, love, but all those negatives in the column may be significant if there is a much higher sample population.  This negative correlation with masturbation frequency and love underscores previous studies of lowered physical and mental health correlating with masturbation.  Penile-vaginal intercourse (I’m just going to call this measure ‘intercourse’ to save my fingers) though shows very strong positive correlations with the quality factors while noncoital sex (all sex behavior minus penile-vaginal intercourse and receptive anal sex) didn’t correlate to any of the quality components.

The authors of the study argue that this is a consequence of our evolutionary history, that activities directly related to gene propagation will be rewarded differently than those that were not.  From the authors: “The results support the hypothesis that exclusively the one potentially reproductive sexual behavior is differentially rewarded at the interpersonal level through the promotion of relationship quality.”

This could be true or it could be that couples with higher satisfaction more routinely participate in intercourse, or there could be a combination of both of these ideas that contribute to “a virtuous circle…in which greater penile-vaginal intercourse frequency (and penile-vaginal intercourse orgasm) leads to a better relationship, which further supports penile-vaginal intercourse frequency (and penile-vaginal inter-course orgasm).”

This paper continues the growing body of evidence that frequent intercourse (as well as frequent intercourse orgasm) is associated with happier long-term relationships.  I like the approach of this paper, trying to explain the rewards and quality measures in terms of evolutionary reward systems that are operating in the cognitive realm.  For sex therapists and marital counselors this should add to the evidence that not all sexual behaviors are equal leading to targeted therapy for those couples that have sex problems which underlie their relationship problems.

Another point of this study which may be disheartening to some men (because we all have big egos) but shouldn’t be is that the quality of the sex is important as well.  Female intercourse orgasm frequency is highly correlated with the quality measures and in fact of the women surveyed intercourse frequency was very highly correlated (0.89, p < 0.001) with intercourse orgasm frequency.  So to do it well you need to do it often, the old saying of “practice makes perfect” is definitely true for this situation.

An interesting piece of data I would have liked to see with this study would be penis length (because let’s face it, all guys wanna know the truth) of the male partners.  We hear a lot about sexual satisfaction and penis size but I would have liked to see how relationship quality measures related to penis size in this instance, a look beyond just the sexual pleasure.  True the data wouldn’t have been instructive since this wasn’t the study’s aim but it would have been a fun aside to look at and maybe a publication in the future off of already collected data.

Costa, R., & Brody, S. (2007). Women’s Relationship Quality is Associated with Specifically Penile-Vaginal Intercourse Orgasm and Frequency Journal of Sex & Marital Therapy, 33 (4), 319-327 DOI: 10.1080/00926230701385548