The Cry It Out Method: What Parents Need to Know

Few parenting topics generate as much heat as cry it out. It's been called damaging, desperate, cruel, and life-changing — sometimes by the same people at different stages of the sleep deprivation journey. If you're trying to work out whether this approach is right for your family, you deserve an honest, research-grounded answer rather than someone's strongly-held opinion.

Quick answer: Cry it out (CIO), also called extinction sleep training, involves placing your baby in their cot awake at bedtime and not responding to crying until morning or a pre-set time. Multiple large-scale studies find no evidence of long-term harm when used at appropriate ages (typically 5–6 months+). It is one of the most studied and most effective sleep training approaches, and it is also genuinely hard to implement.

What "Cry It Out" Actually Means

The term "cry it out" is used loosely and often confusingly. In clinical settings, CIO usually refers to extinction — placing your baby in their sleep space at bedtime and not returning until morning, regardless of crying. There are no check-ins.

This is different from graduated extinction (the Ferber method), where parents return at gradually increasing intervals. Both methods allow crying, but they're not identical — graduated extinction involves more parental involvement than pure CIO.

When parents say "we did cry it out," they often mean they used some version of graduated extinction. It's worth clarifying which approach you're researching, because the evidence and the experience differ.

What Does the Research Actually Say?

This is the heart of most parents' worry, and the research has become considerably clearer over the past decade.

A landmark 2016 Australian study published in Pediatrics — one of the most rigorous to date — randomised 43 infants aged 6–16 months to either graduated extinction, bedtime fading, or no intervention. At 12-month follow-up, there were no significant differences in emotional behaviour, parent-child attachment, or child stress hormone levels between the groups. The sleep training groups slept better; nothing else measurably differed.

A 2020 meta-analysis in Sleep Medicine Reviews, examining multiple studies across thousands of children, similarly found no evidence of negative long-term outcomes from extinction-based sleep training, and significant improvements in infant sleep and maternal depression scores.

The concern that CIO causes emotional damage or disrupts attachment comes largely from research on severe institutional neglect — not from research on parents who were present, responsive during waking hours, and used CIO specifically at sleep time. These are categorically different situations.

When Can You Start Cry It Out?

Age and developmental readiness matter. Most sleep researchers and paediatricians suggest waiting until at least 5–6 months, when:

• •Your baby's circadian rhythm is more established
• •Genuine nutritional need for overnight feeding is reduced (though not always absent)
• •The nervous system has matured enough to sustain the experience without it being overwhelming

Starting before 4 months is generally not recommended by sleep professionals, partly because the developmental prerequisites for independent settling aren't fully in place and partly because genuine hunger needs are still high.

How to Do CIO: A Simple Framework

Before you start:

• •Ensure your baby has no illness, isn't teething acutely, and hasn't had a major disruption (travel, new sibling) in the past week
• •Have a conversation with your partner so you're aligned — one person caving on night two undoes the work
• •Set a timeframe mentally: commit to at least five to seven days before evaluating

The first night:

1. •Run your full bedtime routine as usual — bath, feed, story, whatever your sequence is
2. •Place your baby in the cot awake and drowsy
3. •Say your goodnight phrase warmly and leave the room
4. •Do not return until morning (or a minimum time you've agreed on, such as 6 a.m.)

What to expect: The first night is typically the hardest. Crying may last 45–90 minutes for some babies. This is painful to hear. Most parents find that sitting somewhere they can't hear as clearly, turning on the monitor audio while avoiding the video, or having a partner handle the first night helps them get through it.

Night two: Usually significantly shorter — often 20–40 minutes.

Night three and beyond: Most babies are falling asleep with minimal or no crying within five to seven nights.

Pure CIO vs Graduated Extinction: Which Is Better?

There's no universally "better" — only what fits your family. Pure CIO tends to produce faster results because there are no check-in visits that can accidentally restimulate your baby. Graduated extinction takes longer but some parents find it more tolerable because they're doing something.

Research doesn't show one as more effective than the other in the long term. The approach you can actually implement consistently will always beat the theoretically better approach you abandon on night three.

Common Concerns Addressed

"My baby will think I've abandoned them." A secure attachment is built over thousands of daily interactions across months and years. It is not damaged by several nights of crying at bedtime while you remain accessible and responsive during all other waking hours. The research bears this out clearly.

"It will make them more anxious." Studies measuring cortisol levels and long-term behavioural outcomes have not found elevated anxiety in children who were sleep-trained in early infancy. The 2016 Pediatrics study specifically tested this.

"My baby will cry forever if I don't go in." They won't. Crying typically diminishes substantially by nights three to five, and most babies fall asleep independently within a week. The extinction curve is real.

"We tried it and it didn't work." Occasionally CIO isn't effective — usually because it wasn't implemented consistently (a feed or a pick-up partway through teaches the baby that crying long enough gets a response), or because there's an underlying issue (hunger, illness, reflux) that needs addressing first.

When CIO Is Not Right

Cry it out is not appropriate for:

• •Babies under 4–5 months
• •Babies who are unwell or in the acute phase of teething
• •Situations where the parent genuinely cannot tolerate any crying — because inconsistency makes the process significantly harder and more distressing for everyone
• •Families where another child in the room would be severely disrupted

If you've tried CIO and felt it genuinely wasn't working for your family — not just that it was hard, but that something felt wrong — it's worth trying a more graduated approach or speaking to a sleep consultant for personalised guidance.

A Word on Guilt

The reason CIO generates such controversy is partly that it works, and it involves allowing your baby to cry, and allowing your baby to cry feels terrible. That's worth acknowledging. Most parents who use CIO don't do it because they don't care about their baby's distress — they do it because they're desperate, and because the research tells them it's safe.

If you choose this approach, you're making a considered decision to prioritise the long-term sleep health of your baby and your family. That's not cruelty. That's parenting under difficult conditions with the best available information.

This article is based on published research from the American Academy of Pediatrics (AAP), the National Health Service (NHS), and peer-reviewed pediatric sleep studies. It is not medical advice — always consult your pediatrician for individual guidance.