Children exposed to cannabis before birth had more sleep problems at ages 9-10 | Research

The takeaway

In a large study of nearly 12,000 children, prenatal cannabis exposure was associated with multiple sleep disturbances at ages 9-10, including difficulty falling asleep, staying asleep, and excessive daytime sleepiness.

Obstetricians counseling pregnant patients, pediatricians treating childhood sleep disorders, and researchers studying long-term effects of prenatal cannabis exposure.

Prenatal cannabis linked to sleep problems in 9-10 year olds (n=11,875)

What the researchers found

Any prenatal cannabis exposure was associated with disorders of initiating and maintaining sleep, disorders of arousal, sleep-wake disorders, disorders of excessive somnolence, and a summed sleep disorder score (all p<0.03). Daily prenatal cannabis use was specifically associated with excessive daytime sleepiness (beta=0.29, p=0.03). All associations controlled for other prenatal substance exposures and demographic factors.

Why it matters

Sleep disturbances in childhood affect cognitive development, behavior, and health. If prenatal cannabis exposure contributes to persistent sleep problems, it adds urgency to counseling pregnant individuals about cannabis use.

The numbers in context

11,875 children studied. Prenatal cannabis exposure associated with multiple sleep disorder categories (all beta>0.10, p<0.03). Daily prenatal cannabis use associated with excessive somnolence (beta=0.29, p=0.03).

How the study worked

Analysis of 11,875 children ages 9-10 from the Adolescent Brain Cognitive Development (ABCD) Study. Maternal reports of prenatal cannabis use. Child sleep outcomes assessed by parent report. Controlled for prenatal exposure to other substances, maternal education, income, marital status, race, child sex, and age.

What this study cannot tell us

Cross-sectional analysis within a longitudinal study cannot establish causation. Maternal cannabis use was retrospectively self-reported, subject to recall bias. Sleep outcomes were parent-reported, not objectively measured. Residual confounding possible despite controlling for multiple factors.

How to read the evidence

Large well-controlled epidemiological study, but cross-sectional analysis with self-reported exposures and outcomes.

When this study was published

2020 study using ABCD Study data. Adds sleep to the list of potential long-term effects of prenatal cannabis exposure.

The bigger picture

Cannabis use during pregnancy is increasing as perceptions of harm decrease. Long-lasting effects on offspring sleep add to a growing list of potential consequences that should inform prenatal counseling.

Questions still open

Are these sleep effects mediated by changes in endocannabinoid system development? Do sleep disturbances from prenatal exposure improve or worsen as children age? Would objective sleep measurements (polysomnography) confirm parent-reported findings?

Common questions

What types of sleep problems were found?

Children with prenatal cannabis exposure had more difficulty falling and staying asleep, more arousal disorders, more sleep-wake transition issues, and more excessive daytime sleepiness compared to unexposed children.

Could other factors explain these sleep problems?

The researchers controlled for prenatal exposure to other substances (alcohol, tobacco), maternal education, income, marital status, race, child sex, and age. The associations persisted after accounting for these factors.

Read the original research

Prenatal cannabis exposure and sleep outcomes in children 9-10 years of age in the adolescent brain cognitive development SM study.

Sleep health, 6(6), 787-789

View on PubMed ↗Publisher’s paper ↗

Citation

Winiger, Evan A; Hewitt, John K. (2020). Prenatal cannabis exposure and sleep outcomes in children 9-10 years of age in the adolescent brain cognitive development SM study.. Sleep health, 6(6), 787-789. https://doi.org/10.1016/j.sleh.2020.05.006