Will data make you a better parent? This economist and mom thinks so

As a parent, it may be common to hear unsolicited advice from doctors, family and friends on what's best for your baby. Now, a new book is questioning those ideas by breaking down the data on parenting.

"Cribsheet" is written by economist Emily Oster, who gathered the data, crunched the numbers and, in some cases, debunked the most controversial myths about parenthood.

"This book is about helping people use data and combining that with decision making tools," Oster told "Good Morning America."

"Cribsheet" collects the stats on everything from breastfeeding to sleep training. Oster, a mom herself, said there was info that even surprised her -- like the no peanuts rule.

"For many years, people have been given the advice not to give their kids allergens like peanuts very early on, and actually in the last few years we have learned that people should have been given the opposite advice -- that you should give your kids peanuts and other kinds of allergens when they are very small in order to prevent allergies," she said.

Another popular parenting topic is breastfeeding. The American Academy of Pediatrics recommends that infants be exclusively breastfed for about the first six months and provides major health benefits to mom and baby, according to the Centers for Disease Control and Prevention.

But according to Oster, the current data for breastfeeding is not clear for long term health or cognitive benefits -- a finding that Oster said may alleviate some of the struggle or guilt for moms who are unable or choose not to nurse their children.

"I think that breast is great, if that is the thing that works for you and I think that we should help women, support women who want to breastfeed," Oster said. "You can certainly find studies which show that breastfed kids have higher IQ than kids who are not breastfed but it is likely that those results are driven by differences between the moms -- but not by the breastfeeding itself."

Oster's findings also challenge topics like letting your baby cry it out during bedtime and questioning the benefits of stay-at-home versus working parents.

"To the extent that we do have data, it suggests that it doesn't matter for kids outcomes if you choose to work or not," Oster said. "So kids whose parents work have the same kinds of metrices for success as kinds whose parents do not work."

You can read the full excerpt from "Cribsheet" below.

As infants, both my children loved to be swaddled -- wrapped up tightly in blankets to sleep. Our blanket of choice was something called the Miracle Blanket, which involved a complicated wrapping procedure that only Houdini himself could have escaped. We had about nine of these blankets, since we feared we would run out and have to use a swaddle covered in poop.

Swaddling is great, and it can help your infant sleep. But there is a downside: you can't use it forever. At some point, your kid will get too big and you'll have to stop. Now, a first-time parent might not assume that this is a problem, but breaking the swaddle habit is no easy task.

With our daughter, Penelope (kid number one), breaking the swaddle led to sleep regression, followed by a long reliance on a product called the Rock 'n Play Sleeper, which I still have nightmares about. Other parents have told me stories of seeking secret online sources for larger size swaddles. There are women on Etsy who will create a swaddle blanket for your eighteen-month-old. Please note: Just because there is a secret market for something on Etsy doesn't necessarily mean it's a good idea.

One of the features of having a second child is you can have a do-over on all your perceived mistakes. As an “experienced parent,” you can make sure that anything you look back on with regret, you'll fix on this round. At least, that's what I thought. Breaking the swaddle was at the top of my list. I was going to do it right this time.

As Finn (kid number two) approached four or five months old, I made a plan. First, I'd swaddle Finn as usual for a few days, but leave one arm uncovered. Then, a few days later, after he adjusted to that, I'd take the other arm out. Then I'd uncover his legs. Finally, I'd dispense with the whole swaddle. The internet assured me that this way we'd lose the swaddle without also losing any (hard-won) sleeping skills. I was ready to start. I put a date on the calendar and informed my husband, Jesse.

Then, one extremely hot day shortly before the assigned start date, the power went out, and with it the air conditioning. Finn's room was 95 degrees. It was approaching bedtime. I panicked. When fully deployed, the swaddle blanket was many layers of fabric. Finn would roast.

Should I keep him awake in the hopes the power would come back on? It could be days. Should I just swaddle him and figure he'd be hot? This seemed irresponsible and also kind of mean. Should I just hold him while he slept and not put him in the crib at all until it cooled down? This was also very hot, and experience suggested he wouldn't sleep for long in my arms.

My best-laid plans put aside, I put him to bed in a diaper and onesie. No swaddle. I explained it to him as I nursed him to sleep, drenched in sweat.

“Finn, I'm sorry, but it's so hot out! We can't use the swaddle. But don't worry, you can still sleep. I know you can do it! Now you'll be able to suck on your fingers! Won't that be nice?”

With a big smile, I put him in his crib, unswaddled, and left the room. I prepared for the worst. Penelope would have screamed bloody murder. Finn, though, just made a few surprised noises and fell asleep.

Obviously, an hour later the power came back on. By then Finn was sleeping. I asked Jesse if I should go in and swaddle him now. Jesse told me I was nuts, and collected all the Miracle Blankets for the charity bin. As I lay in bed that night, I wondered if Finn would sleep worse now, if I should go dig the blankets out of the bin and wrap him in one. I was tempted to jump on the computer and read stories of swaddle-induced sleep regression, or lack thereof. In the end, I was too hot to follow through, and our swaddle days were over.

As a parent, you want nothing more than to do the right thing for your children, to make the best choices for them. At the same time, it can be impossible to know what those best choices are. Things crop up that you never thought about -- even with a second kid, probably even with a fifth kid. The world, and your child, surprises you all the time. It is hard not to second-guess yourself, even on the small things.

The swaddle-breaking was, of course, a tiny incident. But it illustrates what will be one of the great themes of your parenting life: you have way less control than you think you do. You might ask why, if I know this to be true, have I written a guide to parenting in the early years? The answer is that you do have choices, even if not control, and these choices are important. The problem is that the atmosphere around parenting rarely frames these choices in a way that gives parents autonomy.

We can do better, and data and economics, surprisingly, can help. My goal with this book is to take some of the stress out of the early years by arming you with good information and a method for making the best decisions for your family.

I also hope Cribsheet will offer a basic, data-derived map of the big issues that come up in the first three years of being a parent. I found that hard to come by in my own experience.

Most of us are parenting later than our parents did; we've been functional adults a lot longer than any previous generation of new parents. That's not just a neat demographic fact. It means we're used to autonomy, and thanks to technology, we are used to having pretty much limitless information in our decision-making.

We'd like to approach parenting the same way, but the sheer number of decisions causes information overload. Especially early on, every day seems to have another challenge, and when you look for advice, everyone says something different. And, frankly, they all seem like experts relative to you. It's daunting even before you factor in your depleted postpartum state and the tiny new resident of your home who won't latch onto your breast, sleep, or stop screaming. Take a deep breath.

There are many big decisions: Should you breastfeed? Should you sleep train, and with what method? What about allergies? Some people say avoid peanuts, others say give them to your child as soon as possible -- which is right? Should you vaccinate, and if so, when? And there are small ones: Is swaddling actually a good idea? Does your baby need a schedule right away?

These questions don't die out as your child ages, either. Sleeping and eating just start to stabilize, and then you'll get your first tantrum. What on earth do you do with that? Should you discipline your kid? How? Exorcism? Sometimes it seems like it. You may just need a break for a minute. Is it okay to let the kid watch TV? Maybe one time the internet told you watching TV will turn your child into a serial killer. It's difficult to remember the details -- but maybe don't risk it? But boy, a break would be nice.

And on top of these questions is the endless worrying, “Is my kid normal?” When your children are very little, “normal” is whether they are peeing enough, crying too much, gaining enough weight. Then it's how much they sleep and how, whether they roll over, whether they smile. Then do they crawl, do they walk, when do they run? And can they talk? Do they say enough different words?

How can we get the answer to these questions? How do we know the “right” way to parent? Does such a thing even exist? Your pediatrician will be helpful, but they tend to (correctly) focus on areas of actual medical concern. When my daughter showed no interest in walking at fifteen months, the doctor simply told me that if she didn't walk by eighteen months, we would start screening for developmental delay. But whether your child is so delayed that they need early intervention is different than whether they are simply a bit slower than the average. And it doesn't tell you if late milestones have any consequences.

At a more basic level, your doctor isn't always around. It's three a.m. and your three-week-old will only sleep while you're right next to him. Is it okay to have him sleep in your bed? In this day and age, you're most likely to turn to the internet. Bleary-eyed, holding the baby, your partner (what an asshole -- this is all their fault anyway) snoring next to you, you look through websites, parenting advice, Facebook feeds.

This can leave you worse off than you were before. There's no lack of opinions on the internet, and many of them are from people you probably trust -- your friends, mommy bloggers, people who claim to know the research. But they all say different things. Some of them tell you that, yes, having your baby sleep in your bed is great. It's the natural way to do it, and there's no risk as long as you don't smoke or drink. They make a case that the people who say it's risky are just confused; they're thinking about people who don't do this the “right way.”

But, on the other hand, the official recommendations say definitely not do this. Your child could die. There is no safe way to co-sleep. The American Academy of Pediatrics tells you to put the baby in the bassinet next to your bed. He wakes up immediately.

This is all made worse by the fact that these comments are (often) not delivered in a calm manner. I have witnessed many an intense Facebook group discussion in which a decision about sleep deteriorates into, effectively, judgement about who is a good parent. You'll have people telling you that choosing to co-sleep isn't just a bad decision, it's one that would be made by someone who doesn't care about their baby at all.

In the face of all this conflicting information, how can you decide what is right not just for the baby, not just for you, but for your family overall? This is the crucial question of parenting.

I'm an economist; a professor whose work focuses on health economics. In my day job I analyze data, try to tease causality out of the relationships I study. And then I try to use that data inside some economic framework -- one that thinks carefully about costs and benefits -- to think about decision-making.

We know being a parent means getting a lot of advice, but this advice is almost never accompanied by an explanation of why something is true or not, or to what degree we can even know it's true. And by not explaining why, we remove people's ability to think about these choices for themselves, with their own preferences playing a role. Parents are people, too, and they deserve better.

The goal of this book is not to fight against any particular piece of advice, but against the idea of not explaining why. Armed with the evidence, and a way to think about decisions, you can make choices that are right for your family. If you're happy with your choices, that's the path to happier and more relaxed parenting. And, hopefully, to a bit more sleep.

This book excerpt is from "Cribsheet" by Emily Oster. Reprinted with the permission of Penguin Press, copyright 2019 by Emily Oster.