The Science of Infant Sleep Part I: The First 6 Weeks

For nearly all parents, the first six weeks after their babies are born seem to be the longest and toughest in their lives. Struggling to understand their babies' needs, parents are awakened at random intervals day after day and night after endless night. It is no wonder that sleep is the most common topic discussed during early visits to the pediatrician. Parents want know when their babies will sleep through the night. In this first installment of our new series on the science of infant sleep, we'll take a look at the research related to why infants sleep the way they do at different ages and what, if anything, parents can do to help their babies sleep a little more.

Before we start, it is important for parents to know that we are not likely to provide "the answers" to parents' sleep concerns. Instead, we'll bring you up to speed with the latest information from the ever growing body of research related to infant sleep. We're taking a developmental approach as we did with the series on the development of language. We'll start with the prenatal period through the first 6 weeks.

How Do Babies Sleep Before They Are Born?
Since ultrasound technologies have become so advanced, researchers know far more than ever before about babies' prenatal behaviors. Distinct sleep states are likely to appear during the last trimester of pregnancy with "active sleep" (lighter sleep with rapid eye movements) being dominant. As any mother knows, fetal sleep cycles do not necessarily to coincide with their moms' sleep cycles. Many moms nearing delivery will tell you that their babies' movements wake them up at night.

What Controls Newborn Sleep Patterns?
In older children and adults, sleep cycles are controlled by specific areas in our brains based on circadian rhythms sensitive to light/dark cycles and by other mechanisms that increase the need for sleep after longer periods of being awake. These controls make us more likely to sleep during the night but also allow us to sleep during the day if we've gone too long without sleep. Another control system influences how long we remain in different types of sleep. Newborns, who are just as happy to sleep during the day as at night, do not seem to develop effective circadian rhythms until they are around 6 weeks old or later. They also are unable to stay awake for long periods of time. Parents of newborns think that their babies wake and sleep randomly, and for the most part, that's true.

Light Sleep, Dreaming, and Brain Development
Newborns sleep very differently from adults. They fall asleep dreaming and may keep dreaming for 20 or 30 minutes. We fall asleep into a "quiet" state of sleep and dream more later in the night and close to morning. Because dreaming happens in a lighter state of sleep, newborns are much more likely to wake up in response to noises, changes in temperature, and movement. When they are dreaming, newborns can make quite a few little noises and their eyes, facial muscles, arms, and legs will move a lot. Some babies may wake themselves up by their own movements. That's why swaddling, which restricts babies' movements, can help newborns sleep a little better. As babies get older, they don't move around quite as much when they sleep and swaddling is no longer necessary.

The brain activity related to dreaming is important for babies' development. Babies brains develop in part because of brain activity in response to stimulation. While babies are awake, they get stimulation from what they see, hear, feel, and taste. While they are asleep and dreaming, babies' brains are active, allowing for brain development to continue even when babies can't stay awake for very long. As babies get older and are able to stay awake for longer periods of time, they spend less time dreaming. During quiet sleep, babies move very little and they are harder to wake.

How Can Parents Help Their Newborns Sleep Longer?
Newborns spend a great deal of time in a lighter state of sleep, waking relatively easily. This is important for babies development and makes the baby likely to wake to feed, to stay warm, and to move as needed. Newborns are not much influenced by light and dark cycles and need to feed frequently. All this means that newborns are going to wake up...a lot...and there isn't much that parents can do about it. But, there are a few things that can make this exhausting time just a bit easier.

• Swaddling can help newborns sleep a little longer because they are less likely to wake themselves up


• Breastfeeding mothers should avoid caffeine because newborns take much longer to process caffeine than adults do


• Holding newborns who have fallen asleep until after their bodies and eyes stop moving will help babies stay asleep when they are put down. Babies in quiet sleep are much less likely to wake easily


• Parents should pay attention to their newborns' noises to learn when they are still asleep and just making noises versus when they are waking up for feeding or other care

Even using all of these tips, parents of newborns will find that their babies will wake frequently. The very best preparation is to arrange to get some help from family and friends to get you through this tough time. Fortunately, things change quickly and more sleep is just around the corner.

Next Time: Big Changes in Sleep Patterns (6 to 16 weeks)

Hey, Where is Everybody?

UC Davis is closed down for most of this week so JenB, JenG, Jane, and Kerri are taking a little break. We'll be back next week with our new series on "The Science of Infant Sleep." We'll "see" you then!

Spring is Here & We Have More Readers Than Ever!

Spring is finally here and we couldn't be happier! We have more readers than ever before and we have been getting great comments and questions on our posts.

If you are new to our blog, WELCOME! We hope that you find our posts interesting and we would like to encourage you to explore previous posts. We recommend that everyone read the Baby Behavior Basics (Parts 1, 2, 3, and 4).

There are a few ways you can find older posts:

1. Use the blog archive (on the left side of the page), which lists the title of each post under the year and month it was published.
   
2. If you have a specific topic you are interested in, you can look through the labels that are also listed on the left. For example, if you are interested in newborn sleep, clicking on the newborn sleep label will take you to all of the posts that mention newborn sleep!
3. The final way to read older posts is to use the "older posts" link that can be found at the bottom of the page, on the right side. Clicking this link will take you through the posts, from the most recent to the oldest.
   

Even though we've covered many topics since we started this blog last summer, there is still so much more to discuss. Please send us your questions and we'll try to answer them as soon as possible!

Reader Question: Why Does My Older Baby Hate Her Highchair?

Recently, we received the following questions from a reader:

My 11 month old won't sit in her highchair anymore. She just screams until I let her sit in my lap. Ideas?

It sounds like this mother has a very smart baby who may be trying to "tell" her mother that she wants to be near her while she eats. This baby also may have had a negative experience that she associates with the highchair. Whichever of these is the case, this baby has created a "script" in her mind of what to expect when she is put into the highchair based on her prior experience.

Babies use "scripts" to help them make sense of the world around them. Just as newborns get so excited when they can "predict" when their parents will smile or tickle their tummies, older babies feel happy and secure when they can predict what will happen during more complex activities like mealtime or bath time.

It's possible that this 11-month-old wants her mother to hold her while she eats, and she has learned that when she screams, her mother will pick her up. In the baby's mind, she creates the following script: sit in highchair - scream - mom picks me up - I'm happy. Mealtime is an important time to practice social skills and most babies want to be close to their family members while they eat. Sitting very close to the baby during meals might help. Perhaps this mother has put her baby in the high chair before everyone is ready to sit down to eat and she is confused and overstimulated by all the activity around her. Watching for baby's cues will help. Offering family meals at regular times during the day and keeping them pleasant is important. Perhaps waiting to put the baby in the highchair or having someone sit close to her while she waits will help. As she gets older and new mealtime routines get established, she'll be much more content in the highchair.

On the other hand, if the baby has had a negative experience in the highchair, she may continue to associate the highchair with that bad experience. She may have sat in the highchair and accidentally been pinched by the tray one time, and now every time she gets in the highchair she believes she may be pinched again. There may have been a time when a loud noise or something else had frightened her when she was in the highchair and now, she is frightened every time she gets into the highchair.

There is a solution though! Parents can create a new "script" for their babies by consistently creating a positive experience in the highchair. One way to do this is to let the baby play with a very special toy only when in the highchair. This positive association will build a new script in the baby's mind: Sit in highchair - get to play with special toy - I'm happy. Or her parents might sit close to her for a few minutes for some special one-on-one time or a game right after she is put in the chair. Changing babies' negative scripts takes time and patience. The key is not to go back to the old script while making the new activity as pleasant as possible. Parents may need to reassure and calm their babies with repetitive sounds and a soft touch. Fortunately, most babies will respond fairly quickly when parents are consistent and calm.

Other highchair hints:

• Is the highchair comfortable now that your baby is growing? It may need some adjustment. For toddlers, parents must consider if their babies have outgrown the highchair. There are booster seats with safety straps, or you can remove the tray and push her right up to the table with the rest of the family (as long as the child may be securely strapped into the chair without the tray). Be sure to pay attention to the guidelines that come along with the various chairs and seats.

• How much time does your baby spend in the highchair? Her body is learning new skills (like pulling up to stand) and the drive to practice is strong at this age. I can remember my very active daughter at this age being able to sit in the highchair for maybe 5-10 minutes at a meal. I would have the meal all plated up, put her in the seat, and put the food down. Sometimes she ate quickly, sometimes she would eat only a few bites, then she would start playing which meant she was done.

• This too shall pass. As babies get older, they are able to sit independently in highchairs for longer periods of time. In my family, we didn't always use a highchair. I have fond memories (and pictures) of my (now, almost 3-year old) daughter sitting on her Daddy's lap sharing his dinner. Then she would switch to my lap and have some of mine. Today, she sits in a big girl chair at the table without a problem. Though she still likes to eat off our plates...after she's finished what's on hers.

Next time: More Readers' Questions

Reader Question: How to keep your baby from being grumpy while grocery shopping

Young babies' behavior can be greatly affected by their surroundings. New sights, smells, and sounds can be exciting and sometimes overstimulating to babies. Parents can find addressing changes in babies' moods more difficult when they are not in the comfort of their own home. In the past, we've provided tips about traveling with your baby, visiting friends who don't have kids, and taking your baby to the doctor. Recently, we received this question from a reader: My baby always get fussy in the grocery store. She seems to hate it but I have to take her with me sometimes. I just have to keep going but she gets pretty bad. Can I make it better for her?

Although we don't have enough information to identify exactly what is going on for this baby, there are numerous things that could be overstimulating her. The bright lights, cool temperature, music and announcements playing over the speakers, odors, and the bright colors of the products lining the shelves can quickly saturate a baby's senses. In addition, babies are often fascinated by other shoppers passing by. Even though the grocery store can be an overwhelming place for young babies, shopping trips don't have to lead to major meltdowns. Here are some tips that can help make a shopping trip easier on everybody:

• Plan ahead. Taking your baby out in public when she is tired or hungry increases the likelihood that she'll become irritable. If you know that your baby tends to be happier at a certain time of day, plan to run errands then!
  


• Try to limit stimulation. Going to the store during slow times (at my grocery store, Saturday mornings tend to be pretty calm) can help reduce over stimulation. If the baby is still in the carrier style car seat you can pull the shade up to limit the light shining in her eyes.
  


• Stick to your list. By making a list and sticking to it, you limit the amount of time spent in the store and reduce the risk of over stimulation.
  


• Bring help. If possible, it can be useful to have one person to attend to the baby and another to do the shopping.


• Interact with your baby. Sometimes when we are trying to hurry through the store, it can be easy to overlook our babies' need for interaction. If your baby is giving engagement cues, try talking or singing to your baby while walking up and down the aisles.
  


• Bring a snack. For my toddler, a trip through the grocery store is like torture if she can't nibble on something along the way. We usually bring a little baggy of apple slices, which lasts just long enough for me to get through the whole store.
  


• Dress your baby comfortably - It can be pretty chilly in the store, so bringing a little extra clothing, especially in the summer when your baby may be dressed lightly, could prevent her from getting irritable because she is too cold.
  
  
• Safety first. Remember that grocery carts aren't designed with the safety features found in strollers. Car seats propped up on the seat, and toddlers who can wiggle out of the safety belt can easily fall onto the floor. Always staying with your cart and being aware of your surroundings will help keep your child safe.
  

These are just a few tips that we have found useful. We would love to hear any additional tips you may have!

Coming Soon: A New Series on Infant Sleep

We're getting out our magnifying glasses and studying night and day! By popular demand, we will start a new series of posts on the mysteries of infant sleep. We'll scour the latest research findings to address more of the specific questions that have come our way in the last few weeks. Stay tuned! In the meantime, we'll continue to answer your questions on other topics.

Do Parenting Blogs Need to be Divisive?

Just last week, we spotted a blog that had been highlighted on one of the major news websites. The blog had been written in defense of using baby videos. The author was upset about the backlash against the “Baby Einstein” videos after research indicated they offered no educational benefits for babies. She described her use of YouTube videos to distract her baby when she needed an occasional moment to herself and defended the use of baby videos as beneficial for parents. I was interested in this perspective because I had written a post about the potential for videos to be barriers to interactions between babies and their parents. But the post itself was not what I found to be so remarkable, it was the comments that really opened my eyes to the polarization of parenting that seems to be so extreme these days. After our own posts about sleep training elicited so many passionate comments (a few were unprintable), I felt the need to re-emphasize our purpose and approach for Secrets of Baby Behavior.

I am what you would call a late “baby boomer.” I entered the working world in the late 1970s and had my children in the 1980s. In those days, the biggest parenting controversies were focused on the increasing numbers of working mothers and the benefits and/or adverse effects of placing children in child-care. Working and stay-at-home moms were pitted against each other, both groups certain of their moral ground. How simple that all seems now! Parents today are battling about birthing practices, infant feeding, sleep duration and sleep arrangements, reading duration, media exposure, safety of toys, crying, waking, early education AND working and childcare. No wonder you are all so fed up! It seems with so many people are fighting about parenting issues, our “villages” (reportedly needed to raise children) are at war.

When we wrote the posts about sleep training, we intended to warn parents searching for a panacea for their sleep-deprivation that they might be disappointed. We understand that some families find the “cry it out” methods logical and appealing. For some babies, the process will work but for many others, it won’t or at least, it won’t work for very long. If well-intentioned parents have gone through the stress of the “cry it out” nights without the desired results, what are they supposed to do? Many tired parents end up rocking their babies to sleep every night, or wearily waiting in baby's room with one hand hanging over the side of the crib, or relying on a family bed. Both the “cry it out” parents and the “rock to sleep” parents feel strongly that they have made the very best choice.

The realities of parenting include babies and parents with different needs and personalities. Parents naturally will defend whatever actions work for them; some might dismiss opposing ideas as criticism of their parenting skills. We have no need or desire to judge other parents. Our research has taught us that some parents need additional resources to make informed decisions. We realize that we are not able to solve parents’ sleep problems or provide tips that work for everyone. We appreciate all of the helpful comments and ideas that many of you have shared with us and we worry about those of you with so much frustration and anger.

One last thing…we think you have enough to worry about as parents. We have no wish to add to your stress. We are here to inform and engage you, not to judge you. We have no interest in participating in the blog battles, so we won’t.

Next time: Back to our readers’ questions!

Why We Don't Like "Sleep Training" for Babies: Part II

With this post, we wrap up our 2-part series on the reasons why we don't like "sleep training" systems that come with promises to parents that their use will result in babies' permanently sleeping through the night.

I am going to start with the bad news first. There is no one "system," product, elixir, or gizmo that will make babies sleep magically through the night. Babies will sleep between 12 and 16 hours per day and some will sleep for significant portions of the night even as young as 4 months of age. Many others do not. Now, we don't want you to think that we are suggesting that it is good or healthy for babies to wake up constantly. Healthy babies will slowly but steadily stretch out the time they spend sleeping. All babies are different but here are some guidelines of what parents might reasonably expect:

• Newborns (birth to 6 weeks) wake frequently and erratically. Parents of newborns must be realistic, prepared, and ready to ask for help!
  
• By 2 months, most babies are sleeping longer stretches, but waking 2-3 times during the night.
  
• By 4 months, many babies start to sleep more like their parents, falling asleep into a deeper sleep and sleeping for 4-5 hours at once. Unfortunately, teething and changing routines can increase waking intermittently around this time.
  
• By 6 months, some babies sleep for 6 hours while others are still waking more frequently, though not every night. There are so many changes typically occurring at 6 months, new skills, new activities, new travels, new teeth...older babies sleep well for a few nights, then wake again. It is no wonder that "sleep training" is so popular among parents of babies around this age.
• About 80% of babies sleep through most nights by 1 year of age.

Once past the newborn period, waking that consistently exceeds these rough guidelines might indicate that something is interfering with your baby's ability to sleep. The first step is to check with your doctor to make sure that your baby is healthy and growing well. Some common (non-health- or feeding-related) triggers for waking include:

• Lights from TVs or video games flickering on the wall (steady nightlights are usually ok)
  
• Caffeine in the breastfeeding mother's diet
  
• Changes in daily routine or no consistent routine
  
• Baby is overstimulated or overtired
  
• Too much sleep during the day
  
• The need to practice new motor skills
  
• Noise, but only if it is sudden and quite loud (babies quickly get used to familiar noises)

So what can be done to help older babies sleep longer if sleep training isn't likely to work?

• Establish routines! Repeated activities and experiences are calming to babies and help them establish body rhythms that are closer to those of their parents. Bedtime routines allow babies time to shift naturally from a drowsy state into sleep. Babies will differ in how much time they need to become ready for sleep; many take at least 20 minutes. Believe it or not, you'll miss the bedtime routines when your children outgrow them.
  
• Reduce or eliminate caffeine for breastfeeding mothers (don't worry, you'll get to have that morning mocha again). Babies' bodies take a lot longer to get rid of caffeine than we do. Remember there is caffeine in tea, sodas, energy drinks, and other products. Read labels.
  
• Make sure that baby isn't overstimulated close to bed time (this is easy to do if parents typically get home late from work). Watch for indications that your baby is drowsy and start your bedtime routine right away. If you wait too long, you might end with a screaming, overtired baby who will be less likely to sleep than a baby put to bed earlier.
  
• Make sure that baby spends plenty of time awake during the day. Give babies plenty of chance to be active, moving, and practicing their new skills during the day.
• Include a special bedtime toy in your bedtime ritual, something that is safe to leave with baby as he drifts into sleep.
  
• Don't end your routine with baby being completely asleep. When babies are put down when they are very drowsy but before they are asleep, they may be better at putting themselves back to sleep if they wake in the night. This doesn't work with babies who hate feeling drowsy and resist sleeping at all costs! I had one of those! The trick is that the baby must be very drowsy or very accustomed to this as an end to the night time routine.
  
• Recognize that most babies make noise when drifting to sleep or they are dreaming, don't assume that intermittent noises mean your baby needs you immediately. Give your older baby a few moments to fall asleep or get back to sleep on his own.

We understand what it is like to be sleep deprived working moms. We also realize that families need to make their own decisions about how they deal with their infants' sleep patterns. But, unrealistic expectations about infant sleep may lead to feelings of frustration, resentment, and insecurity for parents who already are under enough stress. Infant sleep duration is not an indicator of parenting skills. Gaining understanding of how babies sleep patterns evolve, using cues, and developing consistent day- and nighttime routines can result in less stress, more sleep, and much happier babies and parents.

Next time: Answers to more reader questions.

Why We Don't Like "Sleep Training" for Babies: Part I

Several of the questions recently asked by readers included requests for more information on how to get babies to sleep longer. That's no surprise, since sleep deprivation is one of parenting's biggest challenges. We've had a few questions specifically about "sleep training" systems that often include claims that their use will result in getting babies to sleep through the night permanently. We'd like to use this post to explain why we think that the use of "sleep training" (especially without understanding more about infant sleep) may be more likely to lead to frustration rather than a full night's sleep.

Younger Babies Need to Wake

As hard as it is to wake so often with newborns and young babies, the little ones must wake up frequently to feed, stay warm, and be healthy. Newborns dream far more than adults, so they stay in a lighter state of sleep for more of the night than their parents. Dreaming plays a part in the development of their brains and the light state of sleep makes sure that babies wake if they need to. Trying to "train" a newborn to sleep longer will not work and may even be harmful.

For the first 6 to 8 weeks, babies fall asleep dreaming and may continue dreaming for 15 or 30 minutes before they fall into deeper sleep. Parents can see their babies dreaming. Their eyes will move and their faces and bodies will twitch. Waiting until babies fall into a deeper sleep before putting them down can help them stay asleep. As babies get older, they will dream less and have longer stretches of deeper sleep but early on, they are going to wake frequently. That's why new parents need so much help at home.

Waking in Older Babies

By the time babies are 4 months old, they fall asleep into a deeper state of sleep and stay asleep longer. Bedtime routines that end in these older babies being slightly awake when put down for the night can help babies and parents get more rest. By the time babies are about 6 months old, most parents believe their babies should be sleeping through the night but many find that this doesn't happen consistently. Around this time, some babies start teething, catching colds, and traveling to see relatives. As the months go by, babies start to fear separation from their parents and develop motor drives that make them want to practice new skills in the middle of the night. Unfortunately, all of these things can result in waking.

Good Parenting and Sleeping Through the Night

We've noticed that parents whose babies sleep through the night sometimes are seen as the "good parents" who don't spoil their children versus parents who are still getting up as "indulgent" or "giving in" to their unreasonable babies. While parents do have a lot of influence on how much or how little their babies sleep, the truth is that babies wake up for lots of reasons, many of which are not under their parents' control. Some babies are very sensitive to changes in stimulation or the discomforts of teething. Others are driven to practice crawling and standing or are fearful of sounds in the dark. Efforts to get these babies to sleep through the night might work, but only for a short time. Now, I'm not trying to tell you that your baby will never sleep through the night! Babies do sleep! The problem is in the belief that you can force a baby to sleep the way you do.

Sleep "Training" versus Understanding Infant Sleep

Some of the sleep training methods require that babies be put in their cribs and left to cry for ever lengthening periods of time. This is very stressful for parents and babies. While these systems might work for a few nights, many parents find that they have to do the "training" over and over again. Bedtime becomes a battle for weeks on end until one day, the baby starts sleeping longer and parents congratulate themselves that the training finally worked. But the baby is also several weeks older and most older babies will sleep for long stretches if their parents don't interfere. From our perspective, understanding how infants sleep and why they wake can go a long way in helping parents cope with their babies' nighttime behavior.

Next time: We'll review some specific tips to help your baby sleep longer at night.

February Baby Quiz Answers

Here are the answers from last week's quiz.

1. How many bones are in a baby's body? Answer: 300. As babies get older, some of the bones join together, which is why adults only have 206 bones.

2. True or False: Babies' brains have more cells than adults? Answer: True. As babies grow and develop, unused cells (or neurons) are eliminated. There has been a lot of fascinating research about brain development over the last few years!

3. On average, babies will triple their birth weight by what age? Answer: 1 year.

4. How many colds does the average child have in the first 2 years? Answer: 8-10.

5. Generally, how loud (in decibels) is a baby's cry? Answer: 110-115. Normal speaking is usually about 60 decibels. The "safe" maximum level of noise is 90 decibels, so it's a good thing the amount of time a baby cries usually peaks at 6 to 8 weeks of age!