Bryan Johnson's Girlfriend Tracks 'Nighttime Erections' with High-Tech 'Tampon'

Kate Tolo, girlfriend of biohacker Bryan Johnson, is using a specialized device to track nocturnal clitoral engorgement, which she likens to "nighttime erections" in women. This effort aims to explore potential links between this physiological response and women's health, including longevity and early detection of medical issues, mirroring some of the research surrounding men's erectile health.

Tolo's chosen method involves a "techno tampon," a $15,700 "research grade erection device" designed to measure blood flow and engorgement within the vaginal tissues during sleep. She has been tracking her own data nightly, noting that the technology is based on research dating back to 1975. "The tech was invented in 1975 and hasn’t changed in 50 years," Tolo stated, highlighting a perceived gap in the advancement of women's health monitoring technology.

Johnson, who famously monitors his own nighttime erections with a $275 device that connects to a smartphone, has expressed support for Tolo's endeavor. He considers his own data a key indicator of vascular health and has noted the disparity between male and female health tracking tools. "My data is only useful to half the population," Johnson said of his nightly erection data. "Kate’s is the first serious attempt to publicly publish the other half."

The scientific basis for Tolo's work draws on decades-old research. Studies from the 1980s indicate that women experience spontaneous increases in vaginal blood flow during sleep, a phenomenon researchers termed "nighttime erections." This occurs as blood flow increases to the clitoris, causing it to swell, similar to the physiological response in males. The clitoris and penis share the same embryonic origin, developing from the same tissue in the first two months of gestation.

Tolo suggests that tracking these nocturnal engorgement cycles could offer significant insights into women's health. One potential application is differentiating between physical and psychological causes of female sexual dysfunction. If nocturnal blood flow is normal but daytime arousal is lacking, it could indicate a psychological component. "The light sensor inside my probe is the same kind smartwatches use to read your heart rate," Tolo explained about her device.

Furthermore, Tolo believes this data could serve as an early warning system for cardiovascular disease, which affects both men and women. In men, erectile dysfunction is a recognized indicator of heart problems, attributed to the smaller arteries in the penis potentially showing signs of plaque buildup before larger arteries in the heart. Tolo posits that a similar correlation might exist for women, given the shared physiological mechanisms.

Dr. Hillary Seger, a member of Tolo's care team, commented on the significance of Tolo's data collection. "In men, the reasoning behind nocturnal tumescence testing has been that if erections still happen during sleep, the vascular and neurological machinery is intact — though even in men the test is more limited than people assume," Seger said. "For women, there is no validated clinical equivalent. Kate’s recordings are the first look I’ve had at how this signal behaves across a full menstrual cycle."

To further explore women's health biomarkers, Tolo developed "the female protocol," a comprehensive system that monitors 1,900 biomarkers across blood, urine, stool, and vaginal microbiome samples, while controlling for diet, sleep, and exercise. This initiative underscores Tolo's commitment to addressing what she views as a significant disparity in health research and technological development for women.