At CES this year, a smartphone-connected pregnancy test turned some heads. But it turns out that use case might not require its own device -- just a Fitbit and a clever online community. As Buzzfeed reported last week, one New York City woman found out she was pregnant after her Fitbit device displayed a mysteriously elevated heartrate, and her husband turned to online discussion site Reddit for answers. 

Buzzfeed reported that the couple, who were trying to conceive, have chosen to remain anonymous because they're still so early in the pregnancy. After the husband bought his wife a Fitbit for the holidays, the woman's heart rate was consistently registering around 110 beats per minute, when she thought her resting heartrate shouldn't be higher than 100 beats per minute. After a Reddit poster -- herself a pregnant woman -- suggested the possibility of pregnancy, the woman took an at-home pregnancy test that confirmed it.

Since activity trackers hit the market a few years back there has been talk about getting surprises from the data -- for instance, in 2013 TechCrunch wrote about how BodyMedia's device could be used to catch cheating spouses. And it's not the first time data tracking has pegged a pregnancy: the 2012 story of Target's algorithms learning about a teenager's pregnancy before her parents did has attained legendary status as a cautionary tale.

But the addition of heart rate to consumer trackers seems to have caused a marked uptick in surprising data revalations. Back in September, a Massachusetts teenager's Apple Watch also registered a surprisingly high heart rate. But in his case, the culprit was rhabdomyolysis, a potentially fatal muscle syndrome that might have led to kidney failure if it hadn't been caught. And last month, an Israeli entrepreneur happened to be wearing a heart rate-tracking Fitbit when his boyfriend dumped him -- allowing him to see a jump from 72 bpm to 88 bpm in his moment of heartbreak.

There is a debate currently, spurred by a recent class-action suit, about the accuracy of Fitbit's heart rate tracker. But cases like this show that there are certainly things to be learned from that data, and they won't always be what we expect.

As for David and Ivonne, the expectant couple, they're expecting their first child in October and they're making the most of their 15 minutes of fame. They'll post updates on Twitter and Instagram under the name @babyfitbit.