Health care professionals should 'screen for and address' prenatal cannabis use disorder
Prenatal cannabis use disorder was linked to increased risk for major adverse neonatal outcomes, according to results of a population-based, retrospective cohort study published in Addiction.
“In this study, we aimed to add new U.S. data to the relationships between prenatal cannabis use and adverse neonatal outcomes and identify heterogeneities in the relationships by mothers’ tobacco use status and race/ethnicity,” Yuyan Shi, PhD, of the Herbert Wertheim School of Public Health and Human Longevity Science at the University of California, San Diego, and colleagues wrote. “Unlike all previous research focusing on use and non-use without considering dose and frequency, we assessed [cannabis use disorder] as a proxy for heavy and/or long-term use. We examined birth outcomes that were commonly included in existing literature as well as infant outcomes after birth that were rarely assessed.”
The investigators analyzed data from 4.83 million mothers who delivered a live singleton birth between 2001 and 2012 and their paired infants, with data collected via mother-infant linked hospital discharge records, as well as from birth and death certificates. A total of 20,237 mothers had prenatal cannabis use disorder according to ICD-9 codes recorded at delivery. Length of gestation, preterm birth, birth weight, neonatal ICU admission, hospitalization within 1 year of birth and death within 1 year of birth served as neonatal outcomes. Shi and colleagues balanced maternal, paternal and infant characteristics when comparing between infants exposed and unexposed to prenatal cannabis use disorder using propensity score matching.
Results showed an increase in cannabis use disorder from 2.8 to 6.9 per 1,000 deliveries between 2001 and 2012. Prenatal cannabis use disorder was linked to increased risk for being small for gestational age (OR = 1.13; 95% CI, 1.08-1.18), preterm birth (OR = 1.06; 95% CI, 1.01-1.12), low birth weight (OR = 1.13; 95% CI, 1.07-1.2) and death within 1 year of birth (OR = 1.35; 95% CI, 1.12-1.62), according to estimates from multivariable regressions in matched samples. Infants whose mothers used tobacco were at increased risk for preterm birth, low birth weight, hospitalization and death linked to prenatal cannabis use disorder compared with infants who mothers did not use tobacco. Infants whose mothers were Hispanic were at increased risk for hospitalization and death, and those whose mothers were non-Hispanic Black were at increased risk for being small for gestational age linked to prenatal cannabis use disorder, compared with those whose mothers were non-Hispanic white.
“Because we are looking only at medical records, there is a lot we don’t know about the mothers and infants in this study,” Shi said in a press release. “But our analysis supports the recommendation that health professionals screen for and address cannabis use disorders in their pregnant clients — to protect both their health and potentially the health of their infants.”
In a related press release, Nora D. Volkow, MD, director of NIH’s National Institute on Drug Abuse, highlighted considerations that may be necessary for prenatal cannabis use.
“While we cannot establish that cannabis use caused negative outcomes in this study, these data reinforce the case for caution around using cannabis during pregnancy,” Volkow said. “Careful analysis of data like these is one way we can responsibly study how cannabis use affects the developing child, all while a natural experiment is playing out across our country in places where cannabis is becoming widely available to pregnant consumers.”