In a small room on campus at UNC Charlotte, women show up, one at a time, to lean back on a padded, reclined table that looks like it belongs in a doctor's office. On a nearby counter are drawers of lab equipment, one of which is labeled Cleopatra, for the queen who supposedly invented the first vibrator by caging bees. On the wall in front of the table is a large television screen. Once the woman is all set up and given detailed instructions, the lights in the room go off, the television comes on, and a woman-friendly pornographic video begins to play. In the glow of the screen, she'll stimulate herself — for science.
This is just one component of UNCC's Women, Immunity, and Sexual Health lab, or WISH, led by health psychologist Dr. Tierney Lorenz. The lab focuses on investigating questions at the intersection of women's sexuality and mental and physical health. This study is aimed at unraveling part of the complex relationship between a woman's reproductive and immune systems.
"One thing we've found is that sexual activity can change the way that a woman's body responds to certain kinds of immune challenges," Lorenz says. "Does sexual arousal potentially protect against certain kinds of sexually transmitted infections?"
The lab also investigates a host of related questions: The immune system is designed to attack and eliminate foreign objects — what prevents that system from attacking sperm and embryos? And how does a woman's sexual history affect the immune system's function? More specifically, would an abstinent woman's immune system interact with sperm and embryos differently than a sexually active peer's
Lorenz's research suggests that sexual activity in women provokes adaptation in their immune systems. During ovulation in sexually active women, antibody production and other infection-fighting functions drop, but there's very little change in the immune function of abstinent women during the same part of the menstrual cycle.
"The immune system has to have some way of knowing, is there a possibility that I might either be getting pregnant or that I might be pregnant? If so, I need to change the way that I respond to invaders," Lorenz explains. "Sexual activity may cue the body to think that conception is possible, and therefore I should do certain things a little bit differently."
Even as she and her colleagues make groundbreaking advances in our understanding of women's physiology, Lorenz says her work constantly reminds her how much we still don't know. She cites one example after another; the mechanism of copper IUDs remains a mystery, same for the notorious arousal-inhibiting effect of antidepressants.
"The way that our bodies work is so poorly understood," Lorenz says, "and there are so many assumptions that women's bodies must operate very similarly to men's, without any data to support that."
She explains that for about 150 years, textbook writers assumed that women's sexual arousal came from the parasympathetic nervous system — the rest-and-relax system — just like men's. In fact, women's arousal is governed by the sympathetic nervous system, which also triggers the fight-or-flight response. Understanding this link allowed Lorenz, who has worked in clinical settings, to reassure sexual-assault survivors that arousal during assault is neither unusual nor an indicator of "wanting it."
That link has also led to hypotheses about the link between women's arousal and some women's responses to rape fantasies and auto-asphyxiation. Even women who hate that they have rape fantasies often find them an effective shortcut to arousal, Lorenz says.
Science is also yet to satisfactorily explain why female bodies are better at achieving multiple orgasms. "Physiology has not explained that," Lorenz says. "I feel like if I were a drug company trying to make the next blockbuster drug, I'd want to figure that out."
Studying questions of female arousal has come with no shortage of challenges. Lorenz describes one example of the phone calls she gets every month or so: "Does your husband know that you're doing this?"
For Lorenz, it's easy to write off the cranks who call her up. What's less easy to write off are the entities that fund her research. "Nobody wants to be the person who funded the vagina study — ever," she says. "We always have to tie our research back to some other health goal." In one grant proposal, at the request of the funding agency, she had to replace the word "sex" over 5,000 times.
She adds that it would be impossible to get funding for a study that investigated how to make sex better. But, she adds, "When I tell people about the work that I do around desire, around pleasure, around interests, they get excited and interested. They think that that's valuable. The money just isn't there."
Even though there remains much to explore, Lorenz says her field has come a long way. She describes how her mentors, just one generation ahead of her, had to fight for credibility and recognition as scientists. Despite the occasional unsolicited phone call, Lorenz says things are different for her. "To the extent that I present myself as a scientist," she says, "people accept that."