Sleep
What sleep training is and is not
The methods differ substantially, the evidence is better than critics claim and narrower than advocates suggest.
Few parenting topics generate as much certainty on both sides, and the actual evidence supports a narrower and less dramatic set of conclusions than either camp.
What the term covers
A range of behavioural approaches to helping a child fall asleep and return to sleep independently, spanning from gradual parent-present methods to structured extinction approaches.
Lumping them together as a single practice is one reason the debate is so confused.
None of them are appropriate for babies under around six months, for unwell children, or during major disruption.
The main approaches
Bedtime fading: temporarily moving bedtime later to match natural sleep onset, then gradually bringing it earlier.
Involves very little crying and has supporting evidence.
Positive routines: establishing a consistent calm sequence, which is effective on its own for some children.
Camping out or the chair method: a parent stays in the room and gradually reduces their proximity and involvement over one to three weeks.
Gradual, slower, and easier for parents who cannot tolerate leaving.
Graduated extinction: checking at increasing intervals.
The most studied approach.
Full extinction: leaving until morning apart from safety checks.
Effective in trials and the one most parents cannot do.
Parental presence and pick-up-put-down variants, which sit between.
What the evidence shows
Stated fairly.
Systematic reviews of behavioural sleep interventions in infants over six months find improvements in sleep onset latency and night waking, and consistent improvements in parental mood and confidence.
A randomised trial with five-year follow-up found no differences in child emotional or behavioural outcomes, attachment security or stress physiology between intervention and control groups.
Studies measuring cortisol during sleep training have produced mixed results and are small.
Critics point out that most trials measure parent-reported sleep rather than objective sleep, that many report only modest effects, and that infants may stop signalling without sleeping more — which is a legitimate methodological point.
The honest summary: these methods generally work for settling, the evidence does not support claims of long-term harm, and the evidence also does not establish that they are necessary.
What it is not
Clearing up common claims.
It is not leaving a baby to cry indefinitely from birth.
It is not required, and many families never do it.
It is not a fix for a medical cause of waking, which should be excluded first.
It is not appropriate under six months.
And it is not a single method, which means blanket statements about it are meaningless.
Before considering it
What should be addressed first.
Rule out medical causes: reflux, allergy, eczema, iron deficiency, ear infection, and obstructive sleep apnoea in a snoring child.
Check the basics: bedtime timing, daytime sleep, room darkness, temperature, and a consistent routine.
Ensure adequate daytime feeding.
Consider whether night feeds are still nutritionally needed, which varies by age and baby.
And consider whether the current arrangement is genuinely a problem or has simply been labelled one by comparison with others.
Doing it, if you do
Practical points that improve the outcome.
Choose an approach both parents can commit to, since inconsistency between caregivers is the most common reason it fails.
Start on a night when nothing else is happening and you have a few clear days.
Keep everything else consistent.
Expect the first two or three nights to be the hardest, with improvement generally over three to seven nights.
Expect regressions after illness, travel and developmental leaps, requiring a brief repeat.
And stop and reassess if there is no improvement after a week or two, or if the child is unwell.
Deciding not to
An equally reasonable position.
Night waking resolves developmentally in every child.
Many families feed and settle at night for years and are content.
The decision should be based on whether the current arrangement is sustainable for the adults, which is a legitimate criterion rather than a selfish one.
And partial changes are available: sharing nights differently, changing only bedtime settling, or dropping one feed rather than all.
The tone worth taking
This subject attracts more judgement than almost any other in early parenting, in both directions.
Parents who use these methods are not neglectful, and parents who do not are not martyrs.
The evidence supports both positions as reasonable, which is an unsatisfying conclusion and an accurate one.
General information only, not medical advice. Consult your health visitor or a qualified clinician before starting any sleep intervention, and rule out medical causes of night waking first.
