Published by Actually Sleeping · Reviewed by Dr. Samantha Abrahamson, PharmD · Review policy · Updated 2026-11-10

Does sleep training work? What the research says

Yes. A review of 52 studies for the American Academy of Sleep Medicine found that 94% reported behavioral sleep interventions were effective, and over 80% of treated children improved, with gains maintained for 3 to 6 months. Randomized trials also found fewer maternal depression symptoms and no evidence of harm to children’s emotional health, behavior or attachment. Most studies involved babies 6 months and older.

The key studies

Study	Design	Main findings
Mindell et al., 2006 (Sleep)	Review of 52 treatment studies for the American Academy of Sleep Medicine	94% of studies reported the intervention worked; over 80% of treated children showed clinically significant improvement, maintained for 3–6 months. Strongest support for unmodified extinction and preventive parent education; further support for graduated extinction, bedtime fading with positive routines, and scheduled awakenings
Hiscock et al., 2007 (Arch Dis Child)	Cluster randomized trial in Melbourne, Australia; 328 mothers who reported an infant sleep problem at 7 months; behavioral strategies taught in structured nurse consultations	Fewer sleep problems at 10 months (56% vs 68%) and 12 months (39% vs 55%), and fewer maternal depression symptoms, than usual care
Hiscock et al., 2008 (Pediatrics)	Follow-up of the same trial at age 2	Fewer intervention mothers had depression symptoms above the community cut point (15.4% vs 26.4%); no marked differences in parenting or child mental health, which the authors read as no evidence of longer-term harm. Sleep problems: 27.3% vs 32.6%
Gradisar et al., 2016 (Pediatrics)	Randomized trial of 43 infants aged 6–16 months: graduated extinction, bedtime fading or sleep education only	Both methods produced large reductions in time to fall asleep; graduated extinction also reduced night waking. Infant cortisol and maternal stress showed small-to-moderate declines compared with controls. No differences in emotional or behavioral problems or attachment 12 months later

What the evidence supports

It works for most families. Babies fall asleep faster and wake their parents less.
Parents benefit. Improved maternal mood is among the most consistent findings.
No harm has been found in the trials that looked, at 12 months and at age 2.
More than one approach works. Check-based, extinction and fading approaches all have support.

The research answers whether behavioral sleep methods work. It does not tell you which details will work for your baby. That is the part Actually Sleeping does: Dr. Sam applies what the evidence supports through a plan written for your baby, with daily support while you carry it out.

What the evidence does not show

It does not work for every child on a fixed script. Over 80% of treated children improved in the review, which means some did not. Plans that are adjusted as the baby responds are the practical answer to that.
It is not a one-time fix for life. In the Melbourne trial, the gap in sleep problems narrowed by age 2. Illness, travel and regressions can bring old habits back.
Evidence under 6 months is thin. Most trial participants were 6 months or older.
Some methods have no trials. Pick-up-put-down and many popular approaches have not been tested directly.

The limits, fairly stated

Small samples and parent report. The 2016 trial had 43 babies, and many outcomes rely on parents’ diaries.
Mixed methods. Families in the Melbourne trial were taught behavioral strategies by nurses, so results reflect being offered sleep help, not one specific method.
Absence of evidence. “No harm found” in studies of a few hundred children is reassuring but cannot rule out small effects or effects in particular children.

What this means for your family

The research supports behavioral sleep help as effective and, as far as has been measured, safe for healthy babies. Safe sleep rules apply every night whatever you choose: on the back, alone, on a firm, flat, non-inclined surface without soft bedding. Your pediatrician is the authority on your child’s health and night feeds.

At Actually Sleeping, Dr. Sam writes a custom plan for your baby, coaches you bootcamp-style before night one, checks in daily, and coaches naps until solid. It is not cry it out and not wait it out. The result is guaranteed 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. Full refund if not. More than 700 families have been coached; 129 of them describe it in video reviews. Book a free consultation to see how the evidence translates into a plan for your baby.

Want this fixed for your baby?

Actually Sleeping is 1:1 coaching: a sleep plan written for your baby by Dr. Sam, bootcamp-style coaching before the first night, and daily check-ins until it is working. 700+ families coached, 129 video reviews, and a written guarantee: 8–12 hours through the night within 14 days, or a full refund.

Book your free consultation → See what families say

Frequently asked

Is sleep training harmful to babies?

Trials have not found harm. A 2016 randomized trial found no differences in emotional or behavioral problems or attachment a year later, with infant cortisol slightly lower in trained babies than controls. A Melbourne trial found no evidence of harm to child mental health or parenting at age 2.

Does sleep training raise cortisol?

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

Do the effects of sleep training last?

A review found improvements maintained for 3 to 6 months, and one trial found fewer sleep problems at 10 and 12 months. By age 2 the gap had narrowed, so the main benefit is earlier relief for the family. Illness and travel can bring old habits back.

Does the AAP recommend sleep training?

The AAP’s safe sleep guidance applies whatever you choose. Its parent site advises that from about 4 months you put babies to bed drowsy rather than waiting until they are asleep, so they learn to fall asleep on their own. Ask your pediatrician about timing.