What Every Parent Should Know About Sleep Training

Sleep training—also called sleep coaching—uses behavioral strategies to help infants learn how to fall asleep independently and sleep for longer stretches. For many parents, sleep training is a lifeline during those exhausting early months. But with conflicting opinions, it’s important to focus on what science says.

1. Sleep Training is Backed by Strong Evidence

Numerous studies confirm that behavioral sleep interventions (BSIs) are effective. A large meta-analysis involving over 1,600 infants found BSIs reduced child sleep problems by half and significantly improved maternal sleep quality¹. Another systematic review noted that these methods also reduce maternal depression symptoms and improve family well-being².

2. Long-Term Studies Show No Negative Effects

One of the most common concerns is whether sleep training harms attachment or causes long-term stress. Fortunately, research shows no such risks. A 5-year follow-up study concluded that infants who underwent sleep training showed no differences in emotional health or parent-child bonds compared to those who didn’t³. While some studies report temporary increases in cortisol (the stress hormone) during initial sleep training, these changes are short-lived and not linked to long-term harm⁴.

3. Timing is Crucial

Most experts recommend starting sleep training between 4 and 6 months of age, when infants begin developing circadian rhythms⁵. A 2024 randomized trial found that providing sleep education to parents at four months resulted in babies gaining nearly 90 minutes of additional nighttime sleep by six months⁶.

4. Different Methods, One Goal: Independent Sleep

There are several effective sleep training methods, including:

• Extinction (Cry-It-Out): Allowing the baby to self-soothe without intervention.
  
  

• Leave and Check: Allowing the baby to cry for pre-determined intervals of time or progressively longer intervals (Ferber method) with brief check-ins.
  
  

• Bedtime Fading: Gradually adjusting bedtime to align with the baby's natural sleep patterns.
  
  

• Gentle Methods: Soothing approaches that minimize crying, such as "pick up/put down" or parental presence techniques⁷.
  
  Evidence shows all methods can be effective when applied consistently, and parents should choose an approach that aligns with their comfort level and their baby’s temperament⁷.

5. Sleep Training Benefits Parents Too

Parental exhaustion is linked to postpartum depression, affecting approximately 1 in 7 new mothers⁸. Sleep training can improve maternal sleep quality and mood without increasing stress or anxiety levels².

6. Better Sleep Supports Baby’s Brain Development

Adequate sleep is essential for infant brain development. Poor sleep in infancy is associated with delays in cognitive function and behavioral regulation later in childhood⁹. By promoting healthy sleep habits, sleep training lays the foundation for better developmental outcomes.

7. Prioritize Safe Sleep

Often when parents are exhausted and overwhelmed, they make decisions out of desperation that can be dangerous for their babies in the night. When they do not know how to get their babies sleeping well independently, they often co-sleep, for example, which increases the risk of infant death by 50%. When parents go through quality sleep training programs or utilize baby sleep coaches, they typically gain the knowledge and tools to create a safe sleep environment that reduces the risk of Sudden Infant Death Syndrome (SIDS)¹⁰. Safety is always first.

How to Be Successful

Consistency with the method of your choice is most essential for sleep training success. Choosing one particular plan and sticking to it is important, versus mixing and matching different methods and tricks you found online. Inconsistency or mixing methods can delay or thwart success altogether. Consulting a baby sleep coach or utilizing a baby sleep program can provide the guidance and support that yield faster results and that increase your likelihood of success.

References

1. Hiscock H, et al. "Long-term Mother and Child Mental Health Effects of a Population-Based Infant Sleep Intervention." Pediatrics, 2008.
   
   

2. Douglas PS, et al. "Interventions for Infant Sleep Problems and Postnatal Depression: Systematic Review and Meta-Analysis." Sleep Medicine Reviews, 2022.
   
   

3. Gradisar M, et al. "Behavioral Interventions for Infant Sleep Problems: A Randomized Controlled Trial and 5-Year Follow-Up." Pediatrics, 2012.
   
   

4. Middlemiss W, et al. "Asynchrony of Mother–Infant Hypothalamic–Pituitary–Adrenal Axis Activity Following Extinction Sleep Training in Infants." Early Human Development, 2012.
   
   

5. Mindell JA, et al. "Recommended Amount of Sleep for Pediatric Populations: A Consensus Statement of the American Academy of Sleep Medicine." Journal of Clinical Sleep Medicine, 2016.
   
   

6. Manonai J, et al. "Effectiveness of Brief Parental Sleep Education to Improve Infant Sleep Duration: Randomized Controlled Trial." BMC Pediatrics, 2024.
   
   

7. Meltzer LJ, et al. "Sleep Training Methods and Their Impact on Infant and Parental Sleep: Systematic Review." Sleep Health, 2023.
   
   

8. Dennis CL, et al. "Prevalence of Postpartum Depression: Systematic Review and Meta-Analysis." Obstetrics & Gynecology, 2017.
   
   

9. Sadeh A, et al. "Infant Sleep Predicts Attention Regulation and Behavior in Preschool Children." Sleep, 2015.
   
   

10. Moon RY, et al. "SIDS and Other Sleep-Related Infant Deaths: Updated 2022 Recommendations for a Safe Infant Sleeping Environment." Pediatrics, 2022.