4-Week-Old Baby

Wow—can you believe four weeks have passed already? Your 4-week-old baby is still very much an infant, but they’re starting to be more aware of their surroundings. As their engagement with you and the world increases, chances are you’ll feel the connection and bond with baby get even stronger. Here are some of the 4-week-old baby milestones, appointments and more to look out for this week.

4-Week-Old Baby Milestones & Development

Growth

In case you’re curious, the average 4-week-old baby weight is 9.2 pounds for girls and 9.9 pounds for boys, according to the World Health Organization. But remember, people come in all shapes and sizes, so if your child is above or below that average, no big deal. The important thing is that their growth continues at a healthy rate. A 4-week-old baby will grow about 0.5 pounds each week, or 1.5 to 2 pounds per month. They’ll get another inch or so taller this month, and even their head will grow about 0.5 inches.

Emerging skills

There are a lot of exciting developments at this stage. Your 4-week-old baby may now be able to see up to a foot away and will look intently at images and objects placed in front of their face, especially if they’re brightly colored or high contrast. They also love tracking objects at least halfway to the midline. Baby’s hearing is fully mature, so they’ll love listening to you sing or talk and will often turn towards the sound of your voice. They may even start making sounds themselves. You might notice that baby at 4 weeks old can lift their head a bit and can now move their head from side to side when doing tummy time. You’ll also likely see them doing more with their hands as they ball them up into fists or bring their hands to their mouth. Just keep in mind that while your newborn is strengthening their coordination, infants this age still make plenty of jerky movements.

4-Week-Old Baby Health

Feeding

By the end of this week, baby may be eating 3 to 4 ounces per feeding every three to four hours for a total of 32 ounces a day. And while there still may not be a set 4-week-old feeding schedule, meal times are probably starting to happen at more predictable intervals. A loose schedule may naturally emerge.

If baby takes a bottle, don’t be tempted in your sleep-deprived state to prop one up in their crib so you can go back to sleep. It’s not only a choking hazard, but it’s also linked with increased rates of ear infections and asthma later on.

Also, while you may not be thinking about dental hygiene before baby’s first tooth has even popped up, it’s actually never too early to start. Some experts recommend gently cleaning baby’s gums with a damp washcloth after every feeding.

Sleep

Though baby is still a ways away from sleeping through the night (sorry!), your 4-week-old baby may start to have some longer stretches, ideally at night. There still isn’t a 4-week-old baby sleep schedule, but, like feeding, a predictable pattern may start to form. Baby needs about 15.5 hours of sleep in a 24-hour period, with about eight or nine of those hours happening overnight.

Continue to develop healthy sleep habits by putting your child down to sleep before they’re fully asleep or overtired, and creating a quiet and calm sleep environment. Is your 4-week-old baby not sleeping? Try putting them down a bit sooner than you’d think; at this age babies still have a wake window) of just 60 to 90 minutes. Even if they seem ready to party, sleep really does beget sleep.

Common ailments

Crossed eyes Some parents worry when they see their 4-week-old baby cross their eyes; sometimes it can even seem like the eyes are going in different directions. But at this age it’s pretty common and not cause for alarm. If it happens a lot you can bring it up at your next pediatrician appointment, but it’s not usually cause for concern unless the eyes don’t straighten out by about 4 to 6 months old. If that’s the case, your child may have strabismus, which is when one eye is stronger than the other. Treatment is non-invasive and effective.

4-Week-Old Baby FAQs

Can 4-week-old babies smile?

There’s nothing better than seeing baby smile. But at this age, those are most likely reflex smiles, which occur randomly. Intentional smiles don’t usually start until about 6 to 8 weeks of age. But honestly, even those quick little grins are enough to melt your heart and are often just what exhausted parents need.

Can I add rice cereal to baby’s bottle?

While this used to be a common practice to help with everything from reflux to better sleep, the American Academy of Pediatrics (AAP) recommends against it. It’s not advised to give infants anything other than formula or breast milk until they’re 4 to 6 months old. Rice cereal in baby’s bottle could cause your 4-week-old baby to gag, may put them at a higher risk for food allergies later on and can result in overfeeding.

Timely 4-Week Topics

When to introduce a bottle

If baby is formula-fed, you’ve probably got the bottle thing down by now. But if your child is breastfed, then you may be wondering when to introduce a bottle. Experts recommend holding off until breastfeeding is firmly established before giving baby a bottle. But especially if you need to return to work sooner rather than later, four weeks could be the appropriate time to start getting them used to a bottle.

Bedtime routine

It’s never too early to start a baby bedtime routine, so if you haven’t gotten into the habit, now is as good a time as any. A predictable pattern can help signal to baby that it’s time for sleep and can help develop good sleep habits as they grow. Since a 4-week-old baby shouldn’t be awake for more than 90 minutes at a time, you’ll want to start getting ready for bed soon after the last feeding of the “day.” There’s no single universal routine that works for every family, but whatever you choose should be calm and help baby wind down. Many parents like to start with a warm bath, followed by a clean diaper, perhaps a baby massage and pajamas. You can read a book or two, sing a lullaby and put baby down on their back—swaddled, if you like—in their crib or bassinet when they’re drowsy but not fully asleep.

Parent Tips

• Make time to connect with your partner. You’re probably not ready for a night on the town or even to be physically intimate, but that doesn’t mean you can’t find other ways to connect with your partner, if you have one. Having a baby changes relationships, and this first month has likely been a period of huge adjustment. Parents are sleep-deprived, stressed and adjusting to their new roles—which is why it’s all the more important to carve out a bit of time for just the two of you. When baby is asleep, make dinner together, dance to a favorite song, play a boardgame or even just cuddle and watch a show. It doesn’t need to be complicated.
• Talk about sex. Speaking of connecting with your partner, sex after birth is often one of the most fraught milestones for new parents. Doctors typically suggest waiting at least four to six weeks after childbirth to resume sexual activity, to account for physical healing—but that’s just a guideline. It doesn’t necessarily mean you’ll be emotionally ready or crave physical intimacy after holding and caring for baby all day. Keep communication open about how you’re both feeling and ease back in when the time feels right.

Products You Need at 4 Weeks

• Bottles. When it comes time to choose a bottle, the options can feel overwhelming. Read up on the baby bottles our parent product testers tried and loved—and consider ordering a few different ones. Babies each have different preferences, and it may take some trial and error before you find the best fit. Remember that a 4-week-old baby probably still needs a slow flow nipple option.
• Parenting books. Whatever baby-related issues you’re up against, there’s a parenting book for that. These well-reviewed options lay out information and guidance based on research and expert advice, and can help you anticipate and plan for what’s to come.
• Baby swing. Whether you’re looking for a way to give your arms a break or help soothe colic, a baby swing can feel like a lifesaver. The calming motion can help ease tears and relax and entertain your little one. Just remember to put the swing to the most reclined setting and move baby to a firm sleep surface should they start to snooze.

Weekly Activity for Your 4-Week-Old Baby

Infants learn about the world through their senses. If you’re wondering how to play with a 4-week-old baby, try to engage baby’s sense of smell and touch, which are well developed at this age. Take their hand and gently move it across different textures. You can try a soft blanket, a smooth box, bumpy bubble wrap, your cheek, sensory toys, stuffed animals—whatever you have around that’s safe for baby to touch. It may seem simple, but this easy baby activity will help your infant develop tactile discrimination (the ability to tell things apart by how they feel), motor skills and cognition growth as new brain connections are made at a rapid pace.