Sleep & Motherhood

Two studies that will be presented later this morning as posters examine issues related to sleep and motherhood.

One study (#0143) reports that although postpartum mothers’ sleep is disturbed and leads to significant daytime consequences, the timing of their nocturnal sleep may be preserved. Results show that the actual bedtimes and wake times of first-time mothers of newborns were positively correlated with their preferred times. Mothers with both a newborn and other children also tended to fall asleep at their preferred time, but they woke up earlier than their preferred time.

Another study (#0243) suggests that parental presence at bedtime appears to be the factor that impacts sleep more than literal co-sleeping. The study involved parents of 29,287 infants and toddlers from 17 countries. Results show that in predominately Caucasian countries, bed sharing was reported by 11.8 percent of parents and room sharing by 22 percent; in predominately Asian countries these figures were 64.7 percent and 86.5 percent. In predominately Caucasian countries, children who slept in a separate room obtained more sleep, woke less at night, had less difficulty at bedtime, fell asleep faster, and were perceived as having fewer sleep problems; only 40.9 percent of their parents were present with them at bedtime.

Last year at SLEEP 2008 the same research team reported that young children in predominately Caucasian countries have earlier bedtimes and obtain more overall sleep than young children in predominately Asian countries. U.S. children had an average bedtime of 8:52 p.m. and averaged 12.9 hours of total sleep time per day.

You can download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.

Teen Bedtimes Associated with Suicide, Depression & Grades

Two studies being presented as posters later this morning examine the negative impact of late bedtimes on teens.

One study (#1064) suggests that parental-mandated bedtimes could help protect teens from depression and suicidal thoughts by lengthening sleep duration. Results show that adolescents with parental-mandated bedtimes at midnight or later were 25 percent more likely (adjusted odds ratio 1.25) to suffer from depression and 20 percent more likely (adjusted odds ratio 1.20) to have suicidal ideation compared with adolescents who had parental-mandated bedtimes of 10 p.m. or earlier. Multivariate models show that sleep duration may have acted as a mediator of these associations; thus short sleep may be a risk factor for depression and suicidal ideation.

Another study (#0161) shows that being a “night owl” or “evening type” – preferring to go to bed late at night and wake up later in the day – is associated with lower academic performance in college and a decline in academic performance from college to high school. Results indicate that evening types had significantly lower first year college GPA (2.84) than “morning types” and “intermediate types” (3.18). They also slept on average 41 minutes less on school nights. For all students, “sleep hygiene” was related to academic performance.

You can download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.