A study in the Aug. 1 issue of the journal Sleep examined prenatal factors that are related to sleep problems in children.
The study involved 289 children born in Finland in 1998; each child was born at term from 37 to 42 weeks of gestation. Sleep was measured by actigraphy for one week when the children were 8 years of age. Parents reported sleep problems and sleep disorder symptoms.
Results link prenatal alcohol exposure to an increased risk of sleep problems in childhood.
Alcohol "exposure" was defined as a mother drinking more than one alcoholic beverage per week during pregnancy.
Children exposed to alcohol before birth were 2.5 times more likely to have a “short” sleep duration of 7.7 hours or less per night. The AASM reports that at 8 years of age children need about nine to 10 hours of nightly sleep.
Children also were 3.6 times more likely to have a low “sleep efficiency” of 77.2 percent or less if they were exposed to alcohol in the womb; sleep efficiency indicates how much of their time in bed was spent sleeping.
“Adverse fetal environment may have lifelong influences on health and behavior,” principal investigator Katri Räikkönen, PhD, told the AASM.
The CDC reports that drinking alcohol during pregnancy can cause a baby to be born with birth defects. About 1 in 12 pregnant women in the U.S. reports alcohol use.
Size at birth also was related to childhood sleep problems; lower weight and shorter length were associated with lower sleep efficiency. The authors report that small body size at birth may reflect disturbances in the fetal environment.
One finding surprised the authors: There was no link between prenatal tobacco exposure and sleep at 8 years of age.
Learn more about sleep and pregnancy on SleepEducation.com.