Women’s health impacts more than just women, it also impacts their families. That's why the addition of a body temperature sensor, specifically aimed at cycle tracking, is such a big deal.
And it's been a long time coming for wearables, most of which offer cycle tracking features that are merely just calendars.
Wearables offer the opportunity to collect biometric data in a passive and non-invasive way. But up until now, this hasn’t been prevalent enough for women-only features.
Apple’s new body temperature sensor will integrate new fertility features, which include body temperature-based ovulation tracking. This will empower women with a more hands-on experience with their reproductive and personal health monitoring.
How Apple’s temperature tracking works
Body temperature changes have long been used to detect basal body temperature changes – which occur due to hormonal shifts during the ovulation cycle.
Historically, women that wanted this insight into their cycle would have to use a thermometer and a personal logbook.
With the Apple Watch Series 8, the Health app will provide retrospective ovulation estimates using body temperature readings.
It packs in two temperature sensors – one on the heart rate array underneath the case, and another at the surface of the display. These measure for external bias in temperature changes (like your hand being under the blanket, for example), and your skin temperature.
First, the Apple Watch Series 8 will establish a baseline over the course of five days. That means it will work out your normal temperature – which varies across individuals.
Every five seconds during sleep, the Series 8 will measure wrist temperature, looking for deviations from your baseline.
It can then retrospectively alert to fertility windows, validate future window predictions, and alert women to menstrual cycle deviations, which can highlight serious issues like PCOS.
Results are displayed in the Health App and can easily be shared with a doctor or health care provider.
Shifting body temperatures can also indicate other health issues, which means the new sensor could have broader health uses too.
Privacy after Wade vs Roe
In a post-Roe vs. Wade world, there are serious considerations for many women about privacy.
Many women have started to delete their third-party cycle tracking apps, for fear of the information being used against them if they tried to seek an abortion in a US state where it's no longer legal.
Apple has tried to alleviate such fears, emphasizing that all health and fitness data from Apple products are encrypted (so even Apple can’t read them) and protected by passcode, Touch ID or Face ID with two-factor authentication activated.
The Apple Watch Series 8 heralds a big tech development for women wanting to know when they are most fertile. Because when it comes to reproductive rights, knowledge is power.
It also marks a commitment to the evolution of female health solutions for the brand, putting power in the hands of women when it comes to family planning.
Suzaan Sauerman is a wearable technology and femtech expert. She created the first headphone with a heart rate monitor with a team at Jabra, designed the user experience for the first true-wireless headphones for Bowers & Wilkins, and smart jewellery for one of the biggest names.
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