February 26th, 2006
Research reported in The New Scientist (and countless other media outlets) recently suggests that penetrative sex is 400 times better than other sexual encounters.
In a study by researchers at the University of Paisley, Scotland and Swiss Federal Institute of Technology in Zurich measured levels of the hormone prolactin in male and female participants who watched erotic films in a lab before engaging in either solo masturbation or intercourse. The research, reported in Biological Psychology stated prolactin levels were 400% higher in both genders post intercourse.
The researchers have concluded from this that penetrative sex is therefore 400 times better than masturbation.
Which might be believable if the research wasn’t so limited. Before you read my take on the research, check out this analysis from Cory Silverberg who explains what’s wrong with the study.
My concerns mirror Cory’s. I’d also add this a small-scale lab-based study of volunteer participants who don’t mind masturbating or having sex in a lab setting (not everyone’s favourite kink). These participants are not going to be representative of wider populations, nor is the study reflective of how we usually masturbate or have sex with a partner. We’re also not told if the same erotic material was shown to those in the masturbation or intercourse groups – showing different erotica might lead to different responses.
The study assumes that there are only two kinds of sex – masturbation, and penetrative heterosexual intercourse. It isn’t clear whether the female participants who masturbated used clitoral only stimulation, or were encouraged only to use vaginal stimulation. It also isn’t clear whether different sexualities might produce different results – would the same findings come from lesbian or gay participants for example?
Although we assume we know what penetrative sex was, do we really? Within this lab study we assume penetration referred to penis/vagina contact – although it could have included penis/anal contact (or a woman penetrating her male partner with a strap-on if you really wanted to add a bit of spice to your lab!). Without making these conditions clear, and also without testing for these variations – we can’t make assumptions about intercourse. The same goes for masturbation – were participants instructed to use their hands or fingers? Were sex toys permitted?
It’s also not clear how this study was run. Surely to gain representative results participants should have undergone both conditions – the masturbation only and intercourse with a partner. But having undertaken one condition they’d be primed for the research, so you’d have to introduce a second variation where half your participants masturbate first, and half have intercourse with a partner, and measure hormone levels after each encounter. Furthermore, you ideally need a control, so participants who don’t masturbate or have sex at all require hormonal measurement following erotic exposure.
I find research that doesn’t bother to fully measure variables frustrating. It will produce data but they aren’t meaningful. Measuring hormones is fine, but it’s a big step from a hormone increase measurement to assume that penetrative sex is 400% better. Participants will have their own views and research needs to capture their thoughts and feelings – either from a questionnaire or in-depth interview. It isn’t clear if these were used within this research.
It’s also concerning when you look at existing sex research data that suggests, for women particularly, that masturbation is rated very positively – often more positively than intercourse. Certainly for women studies consistently show they orgasm more frequently through masturbation, than through penetrative sex with a partner.
Although hormone level increases indicate something’s happening, it’s a big jump top assume that an increase automatically equals a positive change. Hormone increases alone don’t necessarily make sex ‘better’ – and certainly not 400 times better. This reductionist approach is outdated, and whilst it’s predictable that the mainstream media wouldn’t critique it, you might expect something better from The New Scientist.Tweet