Staying on top of the latest recommendations is like, well, keeping up with a baby. Here's what you need to know right now so your little one is both healthy and safe.

new parents holding baby
Credit: Bogdanhoda/Getty Images

My kids were born a little more than three years apart, and when I had my second I was surprised by how much had changed in that short time. I'm not talking about the state of my post-pregnancy breasts (which, let's face it, had changed a lot). And I'm not even alluding to how much my home décor had evolved (from tastefully casual to littered with plastic toys).

Nope—the biggest changes I discovered were the so-called rules on how to raise and care for my baby. "Every year, more research is done, so the guidelines from the American Academy of Pediatrics (AAP), American College of Obstetricians and Gynecologists (ACOG), and other medical organizations often change along with new discoveries," according to Parents advisor Jennifer Shu, M.D., author of American Academy of Pediatrics' Heading Home With Your Newborn: From Birth to Reality.

Whether it's your first baby or it's been several years since you last gave birth, it's always good to consult with your pediatrician for the most current recommendations. These are the key guidelines that have changed in recent years:

Safer Rides

OLD RULE Babies should sit rear-facing in a car seat until their first birthday.

NEW RULE Keep your munchkin sitting backwards until she's at least 2 years old—or until she exceeds the height or weight limit for the car seat.

WHY THE CHANGE The newer guideline—to keep kids rear-facing until 2—actually just clarifies the AAP's recommendation. It has always advised parents to keep kids rear-facing as long as possible, up to the maximum limit of the car seat. But for years, it also cited one year and 20 pounds as the minimum for flipping the seat, which ultimately confused parents and pediatricians into thinking that was the best time to make the switch. It isn't. Infants and toddlers have a big head for their neck and body. As a car slows during an impact, their head and upper neck continue to move forward rapidly while the straps of the car seat hold their body in place. "This motion puts them at risk for head and severe neck injuries," says Parents advisor and pediatrician Wendy Sue Swanson, M.D., executive director of digital health at Seattle Children's Hospital. "A rear-facing car seat can better absorb the impact and prevent paralysis or even death." One study found that children under the age of 2 are 75 percent less likely to die or to be seriously injured in an accident if they are facing backwards.

In fact, rear-facing is even safer for kids over 2. "Most convertible car seats allow for children to be rear-facing until about 35 pounds, so if your 2-year-old is doing well rear-facing and is less than 35 pounds, you can continue to keep him positioned that way," says Dr. Swanson. Don't worry about his legs being squished. "Having legs or knees bent when rear-facing is not a problem—during an accident or otherwise," says Dr. Swanson.

The Pacifier Advantage

OLD RULE Avoid Binkies—they interfere with breastfeeding.

NEW RULE Put your baby down to sleep with a pacifier, even if you're nursing exclusively.

WHY THE CHANGE Although doctors discouraged pacis for years, studies have found that using one at night and during naps reduces the risk of SIDS. Having a pacifier in your baby's mouth helps to keep her airway open. Plus, the sporadic sucking lets your baby stay in a lighter state of sleep, which decreases the chance that she'll stop breathing. "The greatest SIDS risk is before 6 months, so I usually tell parents they can stop using a pacifier around then," says pediatrician and Parents advisor Ari Brown, M.D., author of Baby 411.

Experts once feared that parents would miss a baby's nursing cues when soothing her with a pacifier; we understand now that if a baby is hungry, that trick won't work. And data show that using a pacifier doesn't reduce breastfeeding rates. "Nipple confusion" is a myth. Babies settle themselves by sucking, and we now know they have no problem distinguishing between different types of nipples. "The real issue is that babies suck a bit differently on a pacifier than they do at the breast, so many breastfeeding experts advise using longer-shaped pacifiers—like Soothie brand—over the 'orthodontic' ones to avoid having Mom end up with nipple trauma," explains Dr. Brown.

However, what if your little one won't take a paci? "There's no need to force it on your otherwise contented baby," says Dr. Swanson.

Banned Bumpers

OLD RULE Those pretty crib bumpers keep your baby from banging his head.

NEW RULE Keep all soft bedding, including bumpers, out of the crib.

WHY THE CHANGE Although the AAP officially recommended against using crib bumpers in 2011, many parents still buy matching sets of bumpers, sheets, and dust ruff les. Multiple studies have shown that the extra layer of plush is dangerous because a baby can press his face against it and suffocate. In fact, a study from Washington University School of Medicine, in St. Louis, found that the number of infant deaths related to crib bumpers has tripled in recent years. Researchers have called for a national ban, like the ones put in place in Maryland and Chicago, which have made the sale of most crib bumpers illegal.

"It's a no-brainer: Just don't use them," says Dr. Swanson. "Even if you used them with your other children, the science is clear that they can do more harm than good." Throw them away (don't donate them!) and keep pillows, blankets, and stuffed animals out of the crib as well. All your baby needs is a mattress with a fitted sheet.

Starting Solids

OLD RULE Hold off introducing allergenic foods, such as peanuts and tree nuts, until your child is 3.

NEW RULE Give small amounts of peanut butter to babies in their first year.

WHY THE CHANGE "For a long time, we thought that avoiding peanuts during a child's early development might fend off severe food allergies," says Dr. Swanson. "Unfortunately, the number of cases of food allergies nearly doubled in the last two decades." Further, in early 2015 a study published in The New England Journal of Medicine found that infants who were introduced to peanuts between 4 and 11 months of age had a significantly lower risk of developing a peanut allergy by age 5.

Bottom line: "Any age is okay to introduce these once-forbidden foods so long as there aren't any choking hazards," says Dr. Shu. So feel free to let your little one lick a little nut butter off your finger. One sure thing to keep out of reach of your child until after age 1 is honey (because of the increased risk of developing botulism).

Smile Saver

OLD RULE Use fluoride-free baby toothpaste until age 2.

NEW RULE As soon as your baby gets her first tooth, use fluoride toothpaste.

WHY THE CHANGE Experts used to say "no" to fluoride because they were afraid that babies and toddlers, who couldn't spit well, would swallow too much and get fluorosis, which makes teeth spotted and blotchy. However, lots of toddlers and preschoolers have been getting cavities. The American Dental Association now advises brushing your baby's teeth twice a day with a tiny smear of fluoride toothpaste: We're talking the size of a grain of rice. "Go with rice-size as long as your child can't spit on demand, and move up to pea-size once she can," says Parents advisor Lezli Levene Harvel, D.M.D., a pediatric dentist in Newark, New Jersey. "Some children aren't exactly spitting on demand at 36 months. My nearly 4-year-old now understands how to, and we have moved her up to pea-size."

Term Limits 

OLD RULE  You don't have to wait to meet your baby—you can be induced after 37 weeks.

NEW RULE Unless there's a valid medical reason, it's best to keep your bun in the oven until at least 39 weeks.

WHY THE CHANGE Maybe your due date falls on a major holiday, and you don't want your baby's birthday to have to compete for the spotlight. (Or hey, maybe you do want to have an Independence Day baby—who wouldn't want a fireworks show on her birthday every year?) Perhaps you're a planner by nature and want to know (exactly) when your little bundle will arrive. Finally, maybe you're just so over being pregnant that you want this baby out. No matter what your logic may be for inducing labor, however, doing so for nonmedical reasons prior to 37 weeks is now considered a no-no. "Some due dates are not exact, and your 38-week baby might really be a 36- or 37-week baby who is technically premature, or also called a late-preterm infant," explains Dr. Brown. "These babies risk having immature lungs, poor sucking technique, low blood sugar, and jaundice. That's no way to start life if you can avoid it."

It's why ACOG now advises that you wait until 39 weeks—and not a single day sooner—to induce, unless you have a medical reason. Those reasons might include multiple births or a life-threatening condition such as preeclampsia.

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