Amber Gehring downloaded the app Baby Connect when her son Lincoln was a newborn. She used it to keep track of how long he slept, when he nursed and to note each diaper change. After every doctor's visit, she entered in his height and weight. Milestones such as rolling over, eating with a spoon? A fever spike? They all went in the app.

"We tracked, the first year, pretty much everything," she said.

Seven years later, the Woodbury mom still logs Lincoln's height and weight after his doctor's appointments.

"I've definitely met people who are like, 'I'm not going to track anything, that's ridiculous.' But I felt like it helped me, and it still helps me," said Gehring, who also uses the technology with her second child.

During the past decade, parents have been amassing billions of detailed data points about their babies through a growing number of tracking products. Free and cheap apps, pricey wearables and smart baby monitors can record everything from naps and words heard to sunlight exposure. They also can analyze that data in real time and display it in charts and graphs.

Like Gehring, many parents say the data can be reassuring and can lead to discoveries, such as food intolerances. And, because apps allow multiple caregivers to pull up the same information, parents, day care providers and grandparents can easily be kept in the loop.

Baby tracking is an extension of the "quantified self" movement, led by the more than 25 million of us who buckle on fitness trackers to record our steps, sleep, heart rate and calories burned. As with fitness trackers, the information about infants and young children is fueling research.

Still, not everyone is an advocate. Many pediatricians say that the tracking is often unnecessary and that the devices can come between parents and their children. It also raises concerns about potential privacy issues.

All about baby

Tracking can begin even before a baby is born.

Parents-to-be can use apps to help them conceive, to time contractions during labor and to keep track of the fleeting minutes a baby sleeps during those first weeks. Day care providers can log each toddler's mood, sleep time and number of bathroom trips onto popular apps such as HiMama or Daily Connect. Each entry immediately pops up on the parents' phones.

And the technology is quickly evolving. There's no need to get out a phone anymore: Alexa can log diaper changes. Wearable baby tech products with sweet names such as Starling and Owlet collect data directly from the babies themselves, measuring such things as the number of words heard, blood oxygen levels and sunlight exposure.

The latest monitors also dig into the collected data to make predictions about behavior, such as how long a nap will last or whether the baby will be crabby upon waking. Later this year, Baby Connect plans to allow users to compare their kid's data with all the data collected from other children.

"Our plan is to use this data to put it back into the application so parents can compare what their child is doing with the rest of the people who are using the application," said Baby Connect founder Xavier Launay.

If a child's data end up in the wrong hands, however, comparing and predicting behavior could create problems for them in the future, privacy experts warn.

"Data sets are often linked and used to make inferences about individuals," said Christine Bannan, consumer protection counsel at Electronic Privacy Information Center. "So, for instance, a company could determine that a person's behaviors as an infant are predictive of their behavior as an adult and use that to make adverse decisions about the individual."

That's why Bannan recommends parents use tracking applications only for a limited time and have the option to delete the data. (The most popular tracking apps allow users to delete their data and post privacy policies that detail which cloud computing companies are storing the data and how information is shared or disclosed.)

For Maple Grove mom Heather Arntson, the benefits outweigh the concerns.

"There's so much electronic data that exists in general, I'd be more concerned about electronic medical records getting leaked or hacked than someone finding out whether my son played with blocks or books that day," said Arntson, whose 1-year-old son's day care providers use KidReports.

There clearly are upsides to gathering and analyzing information about babies. Already, scientists are harnessing it to learn more about the first years of life.

"If the 19th century was about coal, and the 20th century was about oil, I believe the 21st century will be about data," said Dr. Pascal Wallisch, a clinical assistant professor in New York University's Psychology Department.

"Seeing the data will transform our lives, I think. Even with something as holistic as mothering and babies sleeping, ultimately, a numbers-based approach can help mothers realize what's normal, what's not normal."

Fitness tracker data have fueled studies on everything from multiple sclerosis to recovery from hip surgery to the effects of exercising while pregnant.

Now Wallisch and other NYU researchers are studying baby sleep cycles using data from more than 1,000 tiny citizen scientists whose parents are Baby Connect users. The project is part of the university's research into whether disrupted infant sleep patterns can be an early sign of autism.

So far, the NYU researchers have gathered data from about 1,000 users (a relatively small sample of Baby Connect's 850,000 users) who agreed to take part in the study and have diligently logged sleep, diapering and feeding. Researchers are hoping to establish a baseline of "normal" baby sleep, Wallisch said. Already the data have yielded one new finding: Overall, babies tend to sleep more at 4 months than they do at 1 month.

"To my knowledge, that was unknown until this study," Wallisch said.

How much is too much?

Some pediatricians maintain that parents are collecting more information than is helpful and putting too much effort into using apps and monitors instead of relying on their own instincts and observations.

"There's a lot of focus on technology, and that may take away from the interaction and the relationships that you're having with your child, and just responding to their needs and being in tune with them," said Dr. Angela Mattke, a pediatrician at Mayo Clinic Children's Center in Rochester. "We've done well for quite a long time of taking care of kids."

The American Academy of Pediatrics (AAP) doesn't recommend that parents of healthy babies purchase smart monitors that track blood oxygen levels, saying that the devices, which have not been proven to reduce sudden infant death syndrome, can alarm parents unnecessarily.

"We think it's TMI, in a way," said Dr. Lauren Crosby, a pediatrician at LaPeer Pediatrics in Beverly Hills and an AAP spokesperson. "I really think it makes parents more anxious. It gives them too much information that they aren't trained to deal with."

In addition, while tracking feeding and diaper changes can be helpful in the first weeks of a child's life, its importance often quickly fades.

"I don't think they [parents] need to take it to the point of documenting everything for a year," said Mattke. "If they're paying close attention to their child — how they're eating, drinking and acting — that should be enough."

Still, baby tracking is appealing because it's easy to do and seems to offer something that parents, especially first-timers, need: peace of mind.

That's what Gehring believes tracking gave her.

"Now that they are at school, I have no idea what's going on with them," she said. "But it made me feel like I knew what was going on, and then if I had any concerns, I had been tracking.

"When you're sleep-deprived, you're like, 'I have no idea how long this has been going on.' But it was data that I could refer to and be accurate."

New York software engineer Steve Hakusa tracked much of his daughter's first year of life, even entering her information into a Google spreadsheet to run a more detailed analysis than that provided by the free app he used.

Hakusa said baby tracking gave him and his wife a net benefit — reassuring them that their baby was nursing well, for example — even if he couldn't always find patterns or trends in her data. But he conceded that tracking technology may be making it easy for parents to be "more neurotic."

In the days of hardcover baby books and height notches on the wall, it took a lot more effort for parents to keep track of a child's development, let alone analyze it for insights.

"We're making it easier to be a helicopter parent," Hakusa said. "That's what a lot of this technology does."

Erica Pearson • 612-673-4726