A Sobering Map of Sexual Liaisons

Teens and sex. For parents, just putting those two words together can provoke anxiety. For Katherine Stovel, it makes for interesting research.

	Katherine Stovel. Photo by Nancy Joseph.

Stovel, associate professor of sociology, has been studying teens’ sexual behavior for the past ten years. One recent study—part of the huge National Longitudinal Study of Adolescent Health (known as “Add Health”)—followed the romantic and sexual liaisons among students attending a high school in the Midwest.

Stovel and colleagues Peter Bearman and James Moody mapped “sexual networks” in the school, essentially diagramming all of the students’ romantic and sexual relations over an 18-month period, as a way to explore issues of disease transmission.

“We know quite a bit about sexually transmitted diseases,” says Stovel. “Now we wanted to know more about the architecture over which those diseases might travel. Would a small group of students be mixing it up with each other while others were not at all sexually active? Or would they all be connected? We didn’t know what to expect.”

The students provided the answers. Questions about their sexual history were collected as part of a larger national survey that covered a range of topics. Interviewers met with each student and remained nearby as the student completed the survey by computer. Students were assigned numbers, rather than using their names, to preserve anonymity.

Questions regarding sexual activity ranged from type of activity to duration of relationships to condom use. Students were asked to identify their sexual partners by identification number, enabling the researchers to map sexual links throughout the school.

Of the 832 students attending this particular school, 573 reported at least one romantic relationship during the covered period. The most striking feature of the students’ sexual networks was the existence of a very large component involving 52 percent of the romantically involved students. This large, linked group presents a worst-case scenario for the potential to spread disease.

A map of the sexual networks at a midwestern high school, with each dot representing a student (pink for female, blue for male), illustrates how a student in a relationship with one classmate may unknowingly be linked to hundreds of others. Click here for larger version of map.

“While many of the students in this component may have had only one partner, their risk for contracting a sexually trans­-mitted disease (STD) may be significantly greater than an individual with multiple partners who is embedded in a smaller, disjoint component,” says Stovel. “STD risk is not simply a matter of number of partners.”

Of course, much of this is lost on the students themselves. They might know their sexual partners’ recent histories, but they are unlikely to recognize how those histories fit into a larger network. “These structures reflect relationships that may be long over, and they link individuals together in chains far too long to be the subject of even the most intense gossip and scrutiny,” says Stovel. Nevertheless, they are real.”

Stovel and many others continue to use data from the Add Health survey to learn more about what affects adolescents’ health status. With UW colleagues Taraneh Shaffi and King Holmes, she is now studying whether condom use during a first sexual experience influences future condom use and other sexual behaviors that impact the spread of STDs.

Stovel compared a nationally representative group of adolescents who had used a condom during their first sexual experience and a group who had not. These students were followed for approximately seven years after their sexual debut; they provided data about their recent sexual history and condom use as well as biological specimens that were tested for various STDs. It turns out that early condom use is an excellent predictor of subsequent use.

“Even controlling for factors such as age of first sexual experience, grades in school, and ethnicity, use of a condom the first time doubled the likelihood of using a condom during the first year of sexual activity,” says Stovel. “We think there is something about the association of sex and a condom that has durability. For these individuals, they’ve always used a condom when they have sex, and that’s just part of what sex is for them.”

The implications are significant and long-lasting. Seven years after debut, both groups had a similar number of sexual partners, but the group that used a condom the first time were half as likely to have an STD.

“Everyone is more protected if there are less STDs around,” says Stovel, “so everyone benefits from this early condom use. Talking to kids about their sexual health and sexual behavior before they are sexually active is important, because we may be able to help them develop habits that will have a long-term effect on them and their sexual partners.”

[Autumn 2005 - Table of Contents]