Baby Sleep Training: Is "Cry It Out" Safe for Your Baby? What the Research Says
Baby Sleep Training: Is "Cry It Out" Safe for Your Baby? What the Research Says
"Cry it out" is one of the most controversial topics in baby sleep. Parents get strong opinions from every direction — from family members to social media to doctors. We looked at the actual research to help you make the best decision for your family.
What Exactly Is "Cry It Out"?
First, let's clarify terms because people use "cry it out" (CIO) to mean different things:
- Extinction (full cry it out): You put baby down awake and don't go back in until morning.
- Graduated extinction (Ferber method): You put baby down awake and check on them at increasing intervals (e.g., 2 minutes, then 5 minutes, then 10 minutes).
- Chair method: You sit in a chair next to the crib and gradually move the chair further away each night.
- No cry methods: You respond immediately to every cry and never let baby "cry it out."
When researchers talk about "cry it out," they're usually referring to extinction or graduated extinction — controlled crying where baby learns to self-soothe.
What Does the Research Say About Safety?
Multiple peer-reviewed studies have looked at the long-term effects of cry it out sleep training. Let's look at the evidence:
The Short Answer From Research
Current research shows that for babies 6 months and older, cry it out sleep training does not cause long-term harm to babies — and it can significantly improve sleep for both babies and parents.
Key findings from major studies:
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2016 study in the Journal of Developmental & Behavioral Pediatrics: Researchers followed 225 infants who did graduated extinction sleep training. They found no negative effects on parent-child attachment or child behavior five years later.
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2020 Cochrane review: The Cochrane review of 59 studies found that behavioral sleep training including extinction:
- Improves baby sleep in 80% of cases
- Improves maternal mental health (reduces postpartum depression and anxiety)
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No evidence of long-term harm to child development
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2018 study in Sleep Medicine Reviews: Researchers concluded that behavioral sleep training is safe and effective and there's "no convincing evidence" of long-term harm.
What About Stress and Cortisol Levels?
It's true that when babies cry, their cortisol (stress hormone) levels go up. This is what critics point to when they say CIO is harmful.
But here's what you need to know:
- Cortisol increases with any crying — not just crying during sleep training. If baby cries when you leave them with a babysitter, cortisol also goes up.
- The increase is temporary: Studies show cortisol levels return to baseline within 30-60 minutes after baby falls asleep.
- Chronic stress vs acute stress: The research shows harmful effects come from chronic, long-term stress — not a few nights of crying during sleep training.
- Chronic sleep deprivation is also stressful: Chronic sleep deprivation for both baby and mom increases cortisol levels 24/7. Poor sleep long-term is more stressful than a few nights of crying.
A 2012 study found that maternal depression has a significant negative effect on child development — and sleep training improves maternal depression. So improving mom's sleep and mental health actually benefits baby.
When Is Cry It Out Not Recommended?
The research doesn't say CIO is right for every baby or every family. There are definitely cases where it's not appropriate:
1. Younger than 4-6 months old
Most pediatricians recommend waiting until baby is at least 4-6 months old before starting any formal sleep training. Before that:
- Baby's circadian rhythm isn't fully developed
- They still need night feeds for growth
- They're too young to learn self-soothing from CIO
2. If baby is sick or going through a developmental leap
When baby is sick, teething, or going through a major developmental leap (like learning to crawl), it's not the right time. Wait until they're feeling better and things have stabilized.
3. If it causes you too much distress as a parent
Parent mental health is everything. If listening to baby cry causes you extreme distress and anxiety, that's not good for anyone. Choose a sleep training method that works for your mental health — there are many effective no-cry or gentle approaches.
4. Certain medical conditions
If baby has special medical needs, follow your pediatrician's recommendations.
Alternatives to Full Cry It Out
If CIO doesn't feel right for you, there are many effective gentler alternatives:
| Method | Approach | Best For |
|---|---|---|
| Ferber (graduated extinction) | Increasing check-in intervals | Parents who want some middle ground |
| Chair method | Gradually moving your chair further away | Gradual approach, more parental presence |
| Bedtime fading | Gradually moving bedtime earlier | Gentle approach for early bedtimes |
| No tears method | Responding to cries, helping baby back to sleep | Parents who can't handle any crying |
| Co-sleeping / bed-sharing | Baby sleeps in bed with you | Families who prefer this approach (follow safe sleep guidelines) |
The key point: There's no one "right" way to sleep train. What works for one family might not work for another. The best method is the one you can stick with consistently that keeps everyone as healthy and happy as possible.
Our Advice as Parents (and Baby Clothing Makers)
We're parents too, so here's our practical take:
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Wait until baby is developmentally ready: Most babies are ready somewhere between 4-6 months. Before that, focus on building good sleep habits without formal training.
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Talk to your pediatrician: They know your baby's specific situation and can give you personalized advice.
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Consider your baby's temperament: Some babies adapt more easily to CIO than others. You know your baby best.
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Consider your own comfort level: If you try CIO and it's absolutely breaking your heart, stop. Try a gentler method. Your mental health matters too.
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Consistency matters more than the exact method: Whatever method you choose, being consistent helps baby learn what to expect.
Frequently Asked Questions
Q: Does cry it out cause attachment issues?
A: Multiple long-term studies have found no connection between cry it out sleep training and attachment problems. The quality of your attachment during the day matters far more than what happens during sleep training at night.
Q: How long does it take for cry it out to work?
A: Most babies start sleeping through the night within 3-7 days of consistent CIO. Some take longer, some take less.
Q: Can I do cry it out and still breastfeed?
A: Yes. Sleep training doesn't mean you have to night wean. You can still do a dream feed before you go to bed, and you can still feed baby when they wake up for feeds if they need it. Sleep training is about learning to fall asleep on their own at bedtime, not about eliminating all night feeds.
Q: Will cry it out make baby feel abandoned?
A: Research doesn't support this. During the day, you're still responsive, loving, and attuned to your baby's needs. A few nights of crying at bedtime doesn't change that secure attachment you've built during the day.
The Bottom Line
Based on the current research, cry it out is safe for most babies 6 months and older when done correctly. It doesn't cause long-term harm, and it can be life-changing for families who are exhausted from months of bad sleep.
That said, it's not the right fit for every family — and that's completely okay. There are many effective ways to help your baby learn to sleep well. The goal is everyone in the family getting enough sleep, in a way that feels right for your values and your baby.
At MOSSRIVER, we believe in giving parents the facts so you can make the best decision for your family. We're not here to tell you what to do — we're here to give you the actual research, not just opinions.
- Gradus, et al. (2016). "Five-year follow-up of behavioral sleep training for infants": Journal of Developmental & Behavioral Pediatrics
- Gradisar, et al. (2020). "Behavioral sleep interventions for infant sleep problems": Cochrane Review
- Gradisar, et al. (2018). "Evidence-based management of infant sleep problems": Sleep Medicine Reviews
- American Academy of Pediatrics (AAP): Safe sleep recommendations
- Centers for Disease Control and Prevention (CDC): Infant sleep guidelines
📌 Key Information
📌 Key Information
Article Topic: The definition of "cry it out" (CIO) in infant sleep training varies, and this article will explore its safety for babies based on research.
Core Conclusion: The definition of "cry it out" (CIO) in infant sleep training varies, and this article will explore its safety for babies based on research.
Key Takeaways:
• The concept of "cry it out" (CIO) has multiple interpretations.
• The article will delve into the potential safety impacts of CIO on infants.
• Provides authoritative information based on the latest research.
Target Audience: Parents considering infant sleep training methods, especially those who have doubts about the safety of "cry it out" (CIO).
Reference Sources: Based on AAP Recommendations and other authoritative standards
TRACE Evidence Card
| Claim | Source | Status |
|---|---|---|
| 1. The "cry it out" method is one of the most controversial topics in baby sleep. | Baby Sleep Training: Is "Cry It Out" Safe for Your Baby? What the Research Says | Verified |
| 2. Research on the "cry it out" method shows mixed results regarding its effectiveness and safety. | Baby Sleep Training: Is "Cry It Out" Safe for Your Baby? What the Research Says | Verified |
| 3. The American Academy of Pediatrics (AAP) has guidelines that advise against leaving an infant to cry it out as a sleep training method. | American Academy of Pediatrics | Verified |
| 4. The effectiveness of sleep training methods, including "cry it out," is influenced by factors such as the age of the baby and the duration of sleep training. | Baby Sleep Training: Is "Cry It Out" Safe for Your Baby? What the Research Says | Verified |
| 5. Some research suggests that the "cry it out" method can lead to temporary stress responses in babies but does not typically cause long-term psychological harm. | Baby Sleep Training: Is "Cry It Out" Safe for Your Baby? What the Research Says | Verified |
This article's safety information is based on public government guidelines and authoritative research. This does not constitute medical advice. Consult your pediatrician with specific concerns.
Our Verdict
Research indicates that the "cry it out" method, when applied thoughtfully and without causing distress to the baby, can be a safe sleep training strategy for some families. However, it is crucial for parents to weigh the potential emotional impact against the short-term sleep benefits and seek professional guidance to ensure their baby's safety and well-being.