Infant sleep problems: A guide for the science-minded parent

© 2008 Gwen Dewar, Ph.D., all rights reserved

Infant sleep problems can make us crazy. In part, that’s because we feel so helpless to fix them. Babies have different sleep patterns than adults, and these differences limit what we can do. For instance, we can’t make a newborn sleep for 8 hours at a stretch. Nor should we try. Babies have their own special physiological needs.

By the same token, we can’t approach baby sleep problems the same way we approach sleep disorders in children. For example, researchers warn that major behavioral interventions—like so-called “cry-it-out” sleep training programs—are inappropriate for infants under 6 months of age (Owens et al 1999; France and Blampied 1999).

But that doesn’t mean there is nothing you can do. For younger babies, there are many safe, gentle tactics for improving sleep. And as babies mature, your options increase.

In this article, I cover

• the most common infant sleep problems

• the most common behavioral causes of these problems

• strategies to improve infant sleep (including “cry it out” methods and their alternatives)

Infant sleep problems: The most common complaints

According to scientific studies of Western infants and their parents (Anders 1992), the most common infant sleep problems are:

• frequent, prolonged night-time awakenings,

• awakening too early in the morning, and, more rarely

• difficulty falling asleep at bed-time.

In some cases, these infant sleep problems are caused by underlying medical conditions. Some of these medical conditions can be dangerous, so it’s important to rule them out with the help of your pediatrician.

But researchers say that the majority of infant sleep problems are caused by environmental factors. This article focuses on the behavioral approach to infant sleep problems.

For information on sleep conditions that require medical treatment, see this overview of the most common organic causes of infant sleep problems.

Troubleshooting: Behavioral causes of infant sleep problems...and some remedies

Defining an infant sleep problem depends a great deal on your baby’s age. Newborn sleep patterns are necessarily different from those of older children, and babies can’t be expected to sleep for lengthy stretches of time—-or consolidate most of their sleep at night—-until they are at least 3 months old. In fact, many healthy infants won’t achieve these milestones until they are 6 months old.

So as you make your way through this list, keep in mind your baby’s age. For instance, if your infant is 8 weeks old, it makes little sense to worry about setting a strict bedtime. But it may be helpful to keep your night-time soothing rituals calm and low-key.

In what follows, I begin with infant sleep problems that can occur at any age. Then I cover infant sleep problems that apply to the later months-—i.e., to infants old enough to sleep at least 5 hours at night.

Infant sleep problems that can occur at any age

1. Baby’s internal clock is out of sync with the natural 24-hour day.

Most babies don’t develop strong, hormonally-driven circadian rhythms until they are 12 weeks old, and some babies may take considerably longer (Jenni and Carskadon 2005; Jenni et al 2006). But regardless of your baby’s age, it makes sense to help her tune her internal clock. Make sure she is getting exposed to sunlight during the morning and afternoon, and keep her away from artificial lights before and during bedtime. In addition, make sure she’s getting the appropriate social cues about day and night. It may be hard for her to learn that the night is for sleeping if she’s getting a lot of stimulation before bedtime (see next item). For more tips, see “How to help baby adapt to the 24-hour day” in my article about newborn sleep.

2. Baby is over-stimulated before bedtime

Physical exercise and other forms of excitement (like animated verbal interactions) rev up the sympathetic nervous system—the system in charge of keeping you alert. So it’s important to avoid these activities before bedtime. Researchers recommend that parents make the last 2-3 hours before bedtime quiet and calm (e.g., Glaze 2004).

3. You are too quick to intervene at night

Babies sometimes make noises—-and may even cry out-—when they are still asleep or only partially aroused. In fact, this can even happen when a baby is experiencing deep sleep—-the part of the sleep cycle in which he is least likely to awaken. If you jump in too soon, you might actually find yourself waking a sleeping baby.

4. Your attempts to soothe the baby are too stimulating

Some parents may inadvertently cause infant sleep problems by making too much of a fuss when they try to put baby back to sleep. If you want your baby to go back to sleep quickly, avoid engaging your baby in a social interaction. Remember—-interacting with you is the most interesting part of your baby’s world! Instead, keep things dark, quiet, and boring.

5. You aren't consistent in your approach

Dealing with infant sleep problems can be exhausting and extremely frustrating. As a result, anxious, sleepless parents may find themselves alternating between overly stimulating soothing techniques and—-when they are overcome with frustration or despair—-withdrawing from infants altogether (France and Blampied 1999). This is confusing for the infant, and may exacerbate infant sleep problems.

If you find yourself in this situation, take the time to create a single, consistent approach to your infant sleep problems. Research the science of infant sleep patterns and then decide what approach(es) are best for you and your baby. It’s hard to stick with a plan if you feel ambivalent about it. But once you are clear about your own expectations, you may find yourself less anxious and frustrated.

Infant sleep problems: After the first 6 months

1. Baby's bedtime is too early

Parents sometimes overestimate infant sleep requirements, and/or attempt to put babies to bed before they are sleepy. As a result, babies have trouble falling asleep.

The remedy for this infant sleep problem is pretty obvious: Don’t put baby to bed until he’s actually sleepy.

But that’s easier said than done, because some babies seem to become less sleepy the longer they stay awake (see below). Perhaps the best approach is to review the scientific evidence about baby sleep requirements and and signs of sleeplessness. This will help you get a realistic estimate of your baby’s sleep needs. If it seems that your baby’s bedtime really is too early, try the gentle infant sleep training programs described below. Otherwise, see the next section...

2. Baby's bedtime is too late

As mentioned above, tired babies and children sometimes become more active as the night wears on. This phenomenon—-called “overtiredness”-—is widely reported by Western parents and baby experts (e.g., Pantley; Ferber 2006). The remedy for this infant sleep problem is straightforward. Review the information about baby sleep requirements and signs of sleeplessness. Then pick an earlier bedtime and help your baby wind down by introducing some soothing, low-key bedtime rituals.

3. Baby's bedtime is too variable

Western sleep researchers often cite irregular bedtimes as the cause of infant sleep problems. According to their thinking, babies have difficulty learning daily rhythms—and may even suffer a kind of “jet lag”—if their bedtimes vary from day to day.

This seems to make sense. However, it’s not clear that fluid bedtimes are perceived as a problem in other cultures. Children’s bedtimes are pretty flexible in many places, from the highlands of Guatemala (Morelli et al 1992) to Mediterranean Europe (Ottaviano et al 1996). And in many non-Western, non-industrialized societies, people don’t observe fixed bedtimes from day to day (Worthman and Melby 2002). Nor do they don’t try to satisfy all their sleep needs in one, consolidated, night-time session. Instead, they sleep in shifts, and may take naps during the day (Worthman and Melby 2002). For most of human history, these patterns were probably typical (Worthman and Melby 2002).

So do irregular bedtimes really cause infant sleep problems? I haven’t found any scientific studies testing the idea. Given that strictly scheduled bedtimes are uncommon in non-Western societies, I suspect that moderate variation—say, an hour or so either way—is no big deal. As long as your baby is getting enough sleep overall—and getting consistent exposure to natural light cues—she’ll probably be fine. From the perspective of maintaining good circadian rhythms, what’s more important is waking up at roughly the same time each morning.

But it also seems plausible that large variations in bedtime could cause infant sleep problems. If, for instance, they cause your baby to wake up at different times each day, your baby may have difficulty with his circadian rhythms. The problem may get worse if he makes up for lost sleep by taking naps late in the afternoon or evening. And if he can’t make up for lost sleep with naps, he may not meet his sleep requirements.

4. Baby is napping too late in the afternoon

It’s hard to fall asleep at night if you’ve only recently awakened from a nap. A study of infants diagnosed with sleep disturbances reported that babies needed less help falling asleep at night when parents lengthened the time between the last nap of the day and bedtime (Skuladottir et al 2005).

5. Baby is hungry at night

Depending on the age of your baby, there may be little you can do about this. Very young infants need to feed frequently (see infant feeding schedule and breastfeeding on demand). However, you may increase your chances of a lengthy nocturnal sleep bout if you feed your baby between 10pm and midnight (Pinilla and Birch 1993).

In an experimental study of breastfed newborns, researchers instructed parents to concentrate feeding their infants between 10pm and midnight (Pinilla and Birch 1993). In addition, researchers instructed parents to delay feeding their infants immediately after they awoke during the night. (This was to be accomplished by doing other tasks—such as changing diapers—first). By this tactic, parents were to gradually increase the time between nocturnal feedings. Researchers also told parents to provide infants with strong cues about day and night.

The intervention appeared to be very successful. Eight weeks after training began, all infants in the treatment group were sleeping quietly from midnight to 5am (Pinilla and Birch 1993). Only 23% of control infants were doing so.

However, the study design doesn’t permit us to tell which of the interventions were important. And we don’t know if the effect was long-lasting. It’s also unclear if going 5 hours without feeding is in the best interest of the 8-week old infant—particularly if the infant is lower-weight. If you’re interested in trying all three aspects of this approach on a very young infant, you should check with your pediatrician first.

But for older, larger infants, the approach may be appropriate. And one aspect of the approach--encouraging babies to “tank up” before bedtime--seems safe for babies of all ages.

6. Baby doesn't know how to "self-soothe"

According to the ideal of most Western sleep researchers, babies should learn how to fall asleep by themselves. And the way to achieve this? Don’t let baby fall asleep in your arms. Instead, at bedtime, put your baby in a crib before she has fallen asleep.

Advocates of this view have many studies on their side. When babies fall asleep at the breast-—or are placed in cribs after they have already fallen asleep—-babies are less likely to soothe themselves back to sleep when they awaken again during the night (e.g., Anders 1979; Anders et al 1992; Ferber 1986; Goodlin-Jones et al 2001).

Pediatrician and sleep researcher Richard Ferber argues that parents who routinely soothe their young children to sleep are training them to associate sleep with parental intervention (Ferber 2006). As a result, children don’t develop their own self-soothing mechanisms. When babies wake up during the night (and all babies do), they cry until their parents come to their aid.

Is this really a problem? It depends on your expectations. From an evolutionary and cross-cultural standpoint, soothing an infant to sleep is the norm. And-—interestingly—-parents who don’t expect their children to fall asleep by themselves are less likely to report that their children have sleep problems (Morelli et al 1992). In part, this may be because such parents co-sleep with-—and breastfeed—-their infants. Night-time soothing episodes are probably less disruptive to a mother’s sleep if her baby is within arm’s reach.

So it seems that each parent must decide for herself how important self-soothing is. For more information about cross-cultural patterns of infant soothing, see my article on baby sleep patterns.

The big picture: Developing an overall approach to infant sleep problems

For babies under 6 months old...

As noted in the introduction, babies under the age of six months aren’t good candidates for major sleep training programs. But you can still do a great deal to prevent infant sleep problems. Try these safe and gentle tactics:

• Establish regular day-time cues. Make sure baby is exposed to daylight and daytime activity. Include baby in the daily hustle and bustle.

• Establish regular night-time cues. As bedtime approaches, shift down from stimulating activities to more passive, sleepy, sedate activities. Dim the lights. And you might introduce special bedtime rituals—-like reading bedtime stories or singing lullabies.

• Massage therapy. Although a variety of cultures practice infant massage, there has been little scientific research on its effects. However, the limited evidence suggests that infant massage may help babies adapt to the 24-hour day (Ferber et al 2002). In a study of newborns, babies who received 14 days of massage therapy (beginning in the second week of life) showed more mature sleep patterns later. At 12 weeks, the massaged infants had higher levels of nocturnal melatonin (Ferber 2002).

• Bathe baby before bedtime—-if this seems to calm him down. A warm bath signals the body to cool down, which aids sleep. But for some babies, bathing is exciting.

• Tank up before bedtime. As noted above, babies may sleep for longer stretches at night if they have full tummies.

• Keep your night-time soothing techniques calm and low-key. Be responsive but boring. Keep lights out, avoid making noise, avoid moving the baby around, and avoid eye contact.

And for more solutions infant sleep problems, see this article on infant sleep aids.

For babies over 6 months old...

Older babies benefit from the same approach as younger babies do. But because they are more mature, you might also consider these gentle sleep training programs. Because they don’t require babies to fall asleep alone, they minimize distress for both parents and infants.

Is "crying it out" a good solution to infant sleep problems?

If you’re dealing with infant sleep problems, you’ve almost certainly heard about sleep training programs that involve some degree of “crying it out.” These programs instruct parents to put their children to bed (while children are still awake) and then leave them alone. If children cry, parents are instructed to ignore their children for the rest of the night (a method called “extinction”) or for short intervals that may be increased over time (a method called “modified” or “graduated” extinction).

Like other major behavioral interventions, these training programs are NOT considered appropriate for infants under 6 months (Owens et al 1999; France and Blampied 1999). For older infants, the programs are controversial.

On the one hand, randomized, controlled studies show that extinction and modified extinction programs are often successful, in that the children who complete these programs are less likely to disturb their parents at night (summarized in Mindell et al 2006). In addition, studies that have attempted to measure the rate of daytime behavior problems after treatment have shown no negative side effects (summarized in Mindell et al 2006).

On the other hand, it’s clear that leaving infants to fall asleep by themselves is not the norm for our species. Throughout human evolution, babies have fallen asleep in the presence of their parents, and, in the majority of modern human societies, babies continue this pattern. For many parents, asking babies to fall asleep alone-—and permitting them to cry unattended—-seems to violate their deepest instincts. In fact, one of biggest problems with extinction sleep training is that parents find it to be too upsetting (France and Blampied 1999).

Moreover, more studies are needed to assess the behavioral effects of extinction training on infants. On close examination, I can find only three extinction studies that measured the daytime behavior for infants under 12 months of age (France 1992; Eckerberg 2004). In these studies, infants under 12 months were treated together with older children (ranging in age from 24 to 45 months). While the overall, daytime behavioral outcomes were positive, it’s not clear how babies under 12 months fared as a subgroup.

This shortcoming is important, because some researchers, pediatricians, and parents are concerned about the psychological and physiological costs of ignoring distressed infants at bedtime (e.g., Sears and Sears 1996). They point out that crying is associated with physiological markers of stress (like elevated heart rate, blood pressure, and cortisol levels) and reduced blood oxygen levels (Levesque et al 2000; Luddington-Hoe et al 2002). We know that long-term stress causes developmental problems. What we don’t know is what effect short-term stress (associated with several nights of crying without parental soothing) may have on infants.

Another concern is that infants under 12 months may not old enough to understand that their absent caregivers haven’t abandoned them. Starting around 6 months of age, babies begin to form strong emotional attachments to their primary caregivers (Eliot 1999). At around 8 months, most babies begin showing signs of separation anxiety—becoming distressed whenever they lose sight of their caregiver (Eliot 1999). This is also the age when many infants that were previously settled at night revert to night awakenings and crying spells (France and Blampied 1999). The first year may be a bad time to try sleep training methods that involve leaving babies to fall asleep by themselves.

These points lead pediatricians like William Sears to ask what a baby who has undergone a “cry it out” programs has actually learned. Certainly, the baby has learned that crying won’t bring her parents to her aid. Possibly, she’s also learned that her parents are insensitive—-that they can’t be trusted to respond to her needs (Sears and Sears 1996).

Given these concerns, perhaps the more conservative approach is to avoid sleep training methods that involve “crying it out” for infants under 12 months. Even sleep researchers that recommend extinction and modified extinction acknowledge that other methods—-like positive routines and parental presence with reduced contact-— may be as effective (Mindell et al 2006).

References: What scientific studies say about infant sleep problems

Adams LA and Rickert VI. 1989. Reducing bedtime tantrums: Comparison between positive bedtime routines and graduated extinction. Pediatrics 84(5): 756-761.

Anders TF. 1979. Night waking in infants during the first year of life. Pediatrics 63: 860-864.

Anders TF, Halpern LF, and Hua J. 1992. Sleeping through the night: A developmental perspective. Pediatrics 90(4): 554-560.

Fauroux B. 2007. What's new in paediatric sleep? Paediatr Respir Rev. 8(1):85-9.

Eckerberg B. 2004. Treatment of sleep problems in families with young children: effects of treatment on family well-being. Acta Paediatr. 93(1):126-34.

Ferber R. 1986. Sleepless child. In: C. Guilleminault (ed), Sleep and its disorders in children. New York: Raven Press, pp. 1410163.

Ferber R. 2006. Solving your child’s sleep problems: New, revised, and expanded edition. New York: Fireside.

Ferber SG, Laudon M, Kuint J, Weller A, Zisapel N. 2002. Massage therapy by mothers enhances the adjustment of circadian rhythms to the nocturnal period in full-term infants. J Dev Behav Pediatr. 23(6):410-5

France KG. 1992. Behavior characteristics and security in sleep disturbed infants treated with extinction. J Pediat Psychol 17: 467-475.

France KG and Blampied NM. 1999. Infant sleep disturbance: Description of a problem behaviour process. Sleep Medicine Reviews 3(4): 265-280.

Glaze DG. 2004. Childhood insomnia: Why Chris can’t sleep. Pediatric Clin N Amer 51: 33-50.

Goodlin-Jones BL, Burnham MM, Gaylor EE, and Anders TF. 2001. Night-waking, sleep organization, and self-soothing in the first year of life. J Dev Behav Pediatrics 224(6): 226-233.

Jenni OG and Carskadon MA. 2005. Normal human sleep at different ages: Infants to adolescents. In: SRS Basics of Sleep Guide. Westchester, Illinois: Sleep Research Society, pp. 11-19.

Jenni OG, DeBoer T, and Acherman P. 2006. Development of the 24h rest-activity pattern in human infants. Infant behavior and development 29: 143-152.

Levesque BM, Pollack P, Griffin BE and Nielsen HC. 2000. Pulse oximetry: What’s normal in the newborn nursery? Pediatric pulmonology 30(5): 406-412.

Luddington-Hoe SM, Cong X, and Hashemi F. 2002. Infant crying: nature, physiologic consequences, and select interventions. Neonatal Network 21(2): 29-36.

McKenna JJ and McDade T. 2005. Why babies should never sleep alone: A review of the co-sleeping controversy in relation to SIDS, bedsharing and breast feeding. Paediatric Respiratory Reviews (2005) 6, 134–152.

Mindell JA, Kuhn B, Lewin DS, Meltzer LJ, Sadeh A and the American Academy of Sleep Medicine. 2006. Behavioral treatment of bedtime problems and night wakings in infants and young children. Sleep 29: 1263-1281.

Mitchell EA, Thompson JMD. 2003. Snoring in the first year of life. Acta Paediatrica, 92(4), 425-429.

Owens JL, France KG, and Wiggs L. 1999. Behavioural and cognitive-behavioural interventions for sleep disorders in infants and children: A review. Sleep Medicine Reviews 3(4): 281-302.

Pantley E. 2002. The no-cry sleep solution: Gentle ways to help your baby sleep through the night. New York: McGraw-Hill.

Reid MJ, Walter AB, and O’Leary SG. Treatment of young children’s bedtime refusal and nighttime wakings: A comparison of “standard” and graduated ignoring procedures. Journal of Abnormal Child Psychology 27: 5-16.

Sadeh A. 1994. Assessment of intervention for infant night waking: Parental reports and activity-based home monitoring. J Consult Clin Psychol 62(1):63-8

Sears W and Sears M. 1996. The fussy baby book: Parenting your high-need child from birth to age five. New York: Little, Brown and Company.

Skuladottir A, Thome M, and Ramel A. 2005. Improving day and night sleep problems in infants by changing day time sleep rhythm: A single group before and after study. Int J Nurs Stud. 42(8): 843-850.

C.M. Worthman and M. Melby. 2002. Toward a comparative developmental ecology of human sleep. In: Adolescent Sleep Patterns: Biological, Social, and Psychological Influences, M.A. Carskadon, ed. New York: Cambridge University Press, pp. 69-117.

If you found this article on infant sleep problems helpful, be sure to check out my other articles on baby sleep.

Content last modified 3/08