One new study put “crying it out” at night to the test. Flinders University in South Australia studied 43 babies who 6 months or older who had had sleep problems. A third of the parents were told to let the baby cry it out once they put the baby in the crib. A third were told to move the bedtime to when the baby naturally falls asleep — bedtime fading. The rest were told to do nothing different (ie, snuggle with the baby in hopes the baby falls to sleep).
The researchers also studied the baby’s cortisol levels to make sure that the babies were not under stress.
What they found was that the babies who were told to cry it out or had the faded bedtime fell asleep between five to 10 minutes after being put in their cribs. The control group went to bed 20 minutes after the original bedtime.
The crying-it-out and bedtime-fading babies also didn’t wake up at night like the control group did.