Wearable device to help couples conceive
Swiss start-up Ava aims to help couples trying to conceive with a Food and Drug Administration-approved bracelet. The Ava bracelet tracks nine variable "physiological parameters," including heart rate and heat loss, to predict "fertility windows" with 89% accuracy. The three million data points collected and sent to a mobile phone give women more information than ever on their fertility, and the longer the Ava bracelet is worn, the more accurate it becomes.

There's a wearable for just about everything these days. Fake nails to help you commute. A strap-on chair for tired physicians. A Pokemon Go-connected band.

Now there's a wearable designed to help women trying to get pregnant.

Ava, a Swiss startup, on Tuesday started shipping a $199 bracelet that tracks a woman's fertility cycles and helps her figure out the optimal time to conceive. The company also offered the first data on how well the product works.

The bracelet uses technology to solve one of the more frustrating problems for some couples: getting pregnant. A healthy, young couple having sex every day has only a 25 percent chance of conceiving in any given month, according to The New England Journal of Medicine. That figure decreases with age, health issues, intercourse frequency and other factors. Ava is intended to provide more control over the reproductive process.

At night, a woman wears the Ava bracelet, which has a 12-hour battery life (but can recharge in an hour), and the device sends 3 million data points it collects to her phone. The Ava app then displays the information through several graphs along with a timeline of her cycle, which depicts when she will be the most fertile. The Food and Drug Administration-approved bracelet tracks nine physical metrics, including heart rate variability and heat loss, to predict a woman's fertility window, or the six days a month when she can get pregnant.

Ava hopes to make fertility tracking effortless with its wearable and connected app. Daniel Winkler

Ava also unveiled some clinical data, including the finding that the bracelet shows 5.3 fertile days per month with 89 percent accuracy. The company boasts that it's the biggest window provided in the niche market of fertility-tracking devices. The longer a woman wears the bracelet, Ava says, the more accurate the prediction will be.

Don't let the stylish, mint green exterior fool you. Ava's bracelet "looks more like a lifestyle device, but it's a medical device," said Lea von Bidder, company co-founder. In March, Ava concluded beta clinical trials of a year-long study at the University Hospital of Zurich. In May, it received FDA approval in the US. The bracelet is a class one medical device, which means the agency believes it poses little risk and requires the least amount of regulatory control.

The Ava bracelet is just the latest in a host of fertility-tracking products. The OVwatch predicts fertility by detecting the sweat secreted by a woman's skin, which fluctuates throughout her cycle, while the ClearBlue Fertility monitor requires women to urinate on a stick, which is linked to a handheld device that records the data points.

Other options don't require as much tech. Some, like Daysy and Yono, depend on a woman taking her basal temperature, or the lowest body temperature achieved during rest, either with an in-ear device that she wears throughout the night or an under-the-tongue thermometer. Women can also use an ovulation stick to find out whether they at their most fertile.

Ava's team asserts that its bracelet has the others beat. Since the wearable tracks nine physiological parameters, it can give a woman even more information than whether she's got a pretty good chance of getting pregnant. Von Bidder also thinks the app's interface is easier to deal with than the pencil and paper method often used by other fertility trackers.

"It's a very different experience," said Jessica, a 26-year-old who used Ava in beta testing, "to wear a watch overnight rather than sneak off in the middle of the work day with a strip and a pee cup."