That should probably be the title of the new study by Cindy M. Meston and David M. Buss of University of Texas at Austin (PDF).
The study is an important one because it does begin to explore people’s conscious, expressed motivations for having sex, a subject that has been largely ignored or taken for granted in the past. We know much more about what kinds of sex people have than we do about why they have it (or why they think they have it).
And when I read the New York Times article about the study and saw that there was such a wide range of reasons people gave, I was excited: it seemed that the researchers were breaking open some interesting ground and finding lots of diversity.
The news coverage only mentioned a few of the reasons, and I wanted to see the whole list of 237, so I downloaded the study, which you can do here (PDF). I skipped straight to the Table 1 (p. 481) labelled “Top 50 reasons why men and women have sex.” And while I was not at all surprised to find pleasure-oriented reasons among the top reasons for both men and women, I was rather surprised that nowhere in the top 50 for either gender was “conceiving.” Then I read the methods section.
Always read the methods section!
The study occurred in two phases. In the first phase, where the actual list of reasons was generated, the sample was slightly more diverse. It included undergraduate and graduate students in psychology and “community volunteers who were participating in several other ongoing studies in the Sexual Psychophysiology Laboratory at the University of Texas.” (The demographic characteristics of these respondents are not broken down in the methods section of the article so we can’t say much about them.)
These participants were given an opportunity to respond to the following prompt: “Please list all of the reasons you can think of why you, or someone you have known, has engaged in sexual intercourse in the past.” Collectively they came up with 715 reasons, and after the repetitious ones were weeded out the researchers were left with the 237 “distinct” reasons they took into phase two of the study.
It was in phase two, the one with the especially skewed population, that respondents were asked to look at each of the 237 “distinct reasons” and, using each one to complete the sentence “I have had sex in the past because…” to indicate whether that statement was true of “none,” “a few,” some,” “many” or “all” of their sexual experiences. For those who had not had sex in the past (27% of women and 32% of men for whom sexual experience data were available reported not having had sexual intercourse, for example) the instruction was to use that same scale to rate the “likelihood that each of the following reasons would lead you to have sex.” In their published study the authors do not distinguish these responses from those of people who were reporting on actual experience, and while I can’t tell whether that had any major influence on the data, it seems to represent a seriously flawed assumption that guesses about what might motivate one to have sex are the same as reports on what actually has motivated one to have sex.
The respondents in that part of the study, the part where the “reasons” were analyzed for frequency and relatedness, the participants were 1,549 undergraduate students enrolled in Introductory Psychology courses. This kind of sampling is fairly common in academic studies, especially psychological ones, but in this case it makes, I think, a very significant difference in the results. And it means that the title of the study, “Why humans have sex,” and the overall interpretation of the data are rather overstretched. I don’t think that the motivations college students might have for having sex are the same as the motivations that married non-students might have, just for example.
The sample is interesting in its homogeneity in other ways too. Ninety-six percent were between 18-22. And most were not married or living with a sex partner. (Only 4% of the women and 2% of the men were married. Only 6% of the women and 5% of the men were living with a sexual partner.)
So at the time these people were filling out their surveys, they represented a group that is generally young, single or dating students who are focused on their educations and perhaps the beginnings of their careers.
This doesn’t sound like “humans” to me. And it doesn’t sound like a good way to make conclusions about the reasons that people have sex.
While the range of 237 reasons that people have sex might be broad enough to encompass most people’s experience, I don’t think that the priorities or motivations of 18-22 year old college students is representative of the priorities or motivations of, say 30-35 year old people in long-term relationships.
And none of this begins to address the hubris of claiming that any study performed on an American sample represents “humans” in general.
Now, the authors of the study do devote two paragraphs in the discussion section (always read the discussion section) to the limitations of their study. Specifically they mention the fact that their study is based on people’s “expressed reasons” thus can’t account for subconscious or unconscious motivations, and that social approval of some reasons and stigma around others might have affected what people were willing to claim about their own motivations. They also mention the limitations of their sample. They write:
“A third limitation pertains to the relative youth of most of the sample. Reasons for engaging in sexual intercourse undoubtedly differ by age cohort … and would be expected to change over the life span. For example, compared with the student sample assessed in this study, we would expect having sex for reproductive purposes to be endorsed much more frequently among 30 and 40 year olds and having sex simply to gain social status to decline with age.”
They also acknowledge the limitation of conducting their study “within a single culture” and simply say that researchers should explore these same issues in a range of other cultures.
If the authors acknowledge these limitations at the end of their study, why am I harping on them? Mostly because the vast majority of folks who hear about this study won’t have read the study itself. They’ll have read news coverage or commentary that quotes from the body of the results, or directly from the tables, and the authors of the study are not terribly cautious with their language in those sections. They talk about “men” and “women” and “people” but not about “male college students” and “female college students” for example. It will be very easy for these findings to be widely misinterpreted.
Still, the authors of the study raise excellent questions for future research to explore, and those questions acknowledge the limitations of their own work. For example, the authors suggest that future research examine whether or not the 13 major clusters of reasons found in this study are found as primary sexual motivations in other cultures as well, and “to what extent do the reasons for having sex change across the life span.”
It would be just as interesting to ask the question “Are we really motivated by the things we think are motivating us. Ironically, on the same page of the Times was an article suggesting that is not likely to be the case!
Note: In another post I’ll try to address some of the actual findings. It is interesting, for example, how few of the reasons are “common” in the sense of representing most people’s experience much of the time! Even among the top 50 reasons, for example, most had mean scores that indicated that people said they were true only for “a few” or “some” of their sexual experiences!
This is also published on SexInThePublicSquare.Org