Bellabeat specializes in creating smart wearable technology for women, and today it is launching its Leaf smart necklace that helps women keep track of their monthly period cycles.

Urška Sršen, cofounder and chief creative officer at Bellabeat, maker of the Leaf.

Above: Urška Sršen, cofounder and chief creative officer at Bellabeat, maker of the Leaf.

Image Credit: Bellabeat

The Leaf hangs around a woman’s neck and measures her motion. It infers from the data it collects, calculating her amount of breathing, sleep, activity, and stress. There’s a ton of competition out there, but most are fitness-oriented, while Bellabeat zeroes in on women’s health and stress.

The Mountain View, California-based startup is the brainchild of Urška Sršen, cofounder and chief creative officer at Bellabeat. The 25-year-old Sršen said in an interview with VentureBeat that the team designed the Limited Edition Leaf and its new accessory collection with women’s jewelry in mind. It is a nature-inspired design, and you can clip the leaf to any chain or wear it with the included silver chain necklace.

The Limited Edition Leaf is inspired by nature, with a sustainably sourced, 7,000-year-old dark Marshwood, embellished with 14k gold leaf plating. Marshwood gains a dark pigment through preservation, when dead trees fall into a marsh and are submerged in silt. It is available in five different chic styles, aimed at appealing to women. It’s about monitoring your health without compromising style, Sršen said.

“It’s smart jewelry that helps you track sleep, activity, and your period cycle,” Sršen said. “This data is especially important when you are trying to conceive, you are pregnant, or you are approaching menopause. It’s important to understand how this data is important to your wellbeing.”

The woman has to be aware of her own cycle and then enter that data into the Leaf’s app. It then sends reminders and tracks measurements related to the cycle. The company says the Leaf monitors your stress level by measuring the rise and fall of your chest when you breathe while wearing the leaf as a necklace. The breathing data is cross-referenced with stress level entries you input into the Leaf app. Over time, the app learns how your breathing correlates with stress.

As for sleep, Leaf monitors the small movements you make while sleeping. It does not, however, have a heart-rate monitor such as devices like Intel’s Basis Peak smartwatch have. That means it has to make inferences.

Bellabeat also has accessories such as leather, sport vegan fiber, and sterling silver and gold-plated bracelets and necklaces. The Leaf can be worn as a necklace, bracelet, or brooch.

Limited Edition Leaf

Above: Limited Edition Leaf.

Image Credit: Bellabeat

“Our goal is to enable you to wear it every day, and to integrate it into your style, so you don’t have to worry about it,” Sršen said. “It is easy to use on a daily basis, and that’s what you have to have for wearables in order to make people willing to use it. We think the future of wearables is that they become more specific to each user.”

The only feedback that the Leaf delivers is a vibration. Those vibrations are associated with an app that can tell you to increase or decrease your activity, or remind you to get more sleep. The Leaf monitors a woman’s monthly menstrual cycle by tracking expected days of the most intense part of the cycle. Through the app, women can share progress toward health goals through social networks.

Sršen said the Leaf becomes smarter by learning your personal habits, and it tailors feedback accordingly, like a best friend or a health coach. The Leaf device has a six-month battery life, and it has a replaceable battery; it is also water resistant. The Leaf costs $250 for the Limited Edition and $119 for the regular Leaf.

Founded by Sršen and Sandro Mur, Bellabeat graduated from Y Combinator’s program in March 2014. Its mission is creating beautiful, innovative products that help women easily track their overall health and wellness and get connected to their body and mind through different stages in life.

Limited Edition Leaf and app.

Above: Limited Edition Leaf and app.

Image Credit: Bellabeat

The consequences of stress can be serious. “Complications can include premature birth, high blood pressure, gestational diabetes and postpartum depression,” said Dr. Tanja Premru-Sršen, an obstetrician/gynecologist who is chief medical officer at Bellabeat (and Sršen’s mother). “I have seen many cases where women who underwent stress reduction therapy saw dramatic increases in their ability to get pregnant.”

The company has raised a round of investment from SV Angel, Universal, Crunchfund, Nicolas Berggruen, Justin Kan, Michael Seibel, Paul Buchheit, Tom Fallows, CherubicVC, and Adrian Aoun. Bellabeat previously created products such as the Shell heart monitor for pregnant women, the original Leaf activity tracker, and the Balance, which is a scale that tracks weight. The company has 30 employees, including some at teams in Zagreb and Hong Kong.

Limited Edition Leaf

Above: Limited Edition Leaf.

Image Credit: Bellabeat