Is sleep training effective? A plain look at the research

The studies that matter most

Study	How it was done	What it found
Mindell et al., 2006 (Sleep)	A review of 52 treatment studies carried out for the American Academy of Sleep Medicine	94% of studies found the intervention worked; more than 80% of treated children improved in a clinically significant way, and this held for 3–6 months. The strongest support went to unmodified extinction and preventive parent education, with further support for graduated extinction, bedtime fading with positive routines, and scheduled awakenings
Hiscock et al., 2007 (Arch Dis Child)	A cluster randomized trial in Melbourne, Australia, with 328 mothers who reported an infant sleep problem at 7 months; nurses taught behavioral strategies in structured consultations	Compared with usual care, fewer sleep problems at 10 months (56% vs 68%) and 12 months (39% vs 55%), plus fewer maternal depression symptoms
Hiscock et al., 2008 (Pediatrics)	Follow-up of that trial when the children were 2	A smaller share of intervention mothers had depression symptoms above the community cut point (15.4% vs 26.4%); there were no marked differences in parenting or child mental health, which the authors interpreted as no evidence of longer-term harm. Sleep problems: 27.3% vs 32.6%
Gradisar et al., 2016 (Pediatrics)	A randomized trial of 43 infants aged 6–16 months assigned to graduated extinction, bedtime fading or sleep education only	Both methods cut the time taken to fall asleep substantially; graduated extinction cut night waking too. Compared with controls, infant cortisol and maternal stress fell by small-to-moderate amounts. No differences in emotional or behavioral problems or attachment were seen 12 months later

What the research backs up

Most families see it work. Babies fall asleep sooner and wake their parents less often.
Parents gain too. Better maternal mood is one of the most consistent results.
The trials that checked found no harm, at 12 months and at age 2.
Several approaches work. Check-based, extinction and fading methods all have support.

Research tells you whether behavioral sleep methods work. It cannot tell you which details will work for your particular baby. That is where Actually Sleeping comes in: Dr. Sam puts what the evidence supports into a plan written for your baby, and supports you daily while you follow it.

What the research does not show

A fixed script does not work for every child. In the review, more than 80% of treated children improved, so some did not. A plan that is adjusted as the baby responds is the practical response to that.
It is not a permanent, one-off fix. By age 2 the difference in sleep problems in the Melbourne trial had narrowed. Illness, travel and regressions can bring old habits back.
There is little evidence under 6 months. Most people in the trials were 6 months or older.
Some methods have never been trialled. Pick-up-put-down and many popular approaches have not been directly tested.

An honest look at the limits

Small groups and parent reports. Only 43 babies took part in the 2016 trial, and many outcomes depend on parents’ diaries.
A mix of methods. In the Melbourne trial, nurses taught families behavioral strategies, so the results reflect being offered sleep help rather than any one method.
Not finding something is not proof. Finding “no harm” in studies of a few hundred children is reassuring, but it cannot exclude small effects or effects in particular children.

What it means for your family

The research shows behavioral sleep help to be effective and, as far as it has been measured, safe for healthy babies. Whatever you decide, safe sleep rules apply every night: on the back, alone, on a firm, flat, non-inclined surface with no soft bedding. Your pediatrician has the final word on your child’s health.

At Actually Sleeping, Dr. Sam writes a custom plan for your baby, gives you bootcamp-style coaching before night one, checks in every day, and coaches naps until they are solid. It is neither cry it out nor wait it out. The result is backed in writing: We guarantee that your baby will sleep 8–12 hours through the night within 14 days of consistent, correct implementation of your sleep plan. If not, you receive a full refund. We have coached more than 700 families, and 129 of them talk about it in video reviews. Book a free consultation to find out how the evidence becomes a plan for your baby.

Want your baby’s sleep sorted?

Actually Sleeping offers 1:1 coaching: Dr. Sam writes a sleep plan for your baby, you get bootcamp-style coaching ahead of the first night, and we check in daily until it works. We have coached 700+ families, collected 129 video reviews, and put our guarantee in writing: 8–12 hours through the night within 14 days, or a full refund.

Book your free consultation → See what families say

Common questions

Does sleep training harm babies?

The trials have found no harm. In a 2016 randomized trial there were no differences in emotional or behavioral problems or attachment a year on, and infant cortisol was slightly lower in trained babies than in controls. A Melbourne trial found no evidence of harm to parenting or child mental health at age 2.

Does sleep training increase cortisol?

In the randomized trial that measured it, infant cortisol showed small-to-moderate declines in the graduated extinction and bedtime fading groups compared with controls, along with small-to-moderate declines in maternal stress.

Are the results of sleep training lasting?

One review found improvements held for 3 to 6 months, and one trial found fewer sleep problems at 10 and 12 months. The gap had narrowed by age 2, so the chief benefit is that the family gets relief sooner. Illness and travel can bring old habits back.

Is sleep training recommended by the AAP?

Whatever you choose, the AAP’s safe sleep guidance applies. Its parent site recommends putting babies to bed drowsy from about 4 months rather than waiting until they are asleep, so that they learn to fall asleep by themselves. Check with your pediatrician about timing.