Cannabis use during pregnancy heightens the risk of adverse birth outcomes such as preterm birth, low birth weight, and requiring neonatal intensive care unit (NICU) care, according to a new study in the journal Addiction.
However, they are not at greater risk of birth defects or death within one year, including sudden unexpected infant death, compared to infants without prenatal cannabis exposure.
The research pooled the results of 57 prior studies published between 1984 and 2023. This included data from almost 13 million infants, of which more than 102,000 had intrauterine cannabis exposure.
Mothers using cannabis were over 1.5 times more likely to have a preterm delivery, and more than 2 times as likely to have a low-birth-weight baby, compared with mothers not using cannabis during pregnancy.
Cannabis exposed newborns were also more than 2 times as likely to require NICU admission than nonexposed newborns.
Maryam Sorkhou, first author of the study and PhD candidate at the at the Institute of Medical Science, University of Toronto, Canada, says: “The global increase in cannabis use among women of reproductive age also extends to pregnant women.”
“We know that THC, the main psychoactive constituent in cannabis, can cross the placenta from mother to foetus and bind to receptors in the foetal brain.
“Our study adds to that knowledge by showing that prenatal exposure to cannabis heightens the risk of several adverse birth outcomes.”
Originally published by Cosmos as Babies exposed to cannabis more likely to be born preterm
Imma Perfetto
Imma Perfetto is a science journalist at Cosmos. She has a Bachelor of Science with Honours in Science Communication from the University of Adelaide.
Read science facts, not fiction...
There’s never been a more important time to explain the facts, cherish evidence-based knowledge and to showcase the latest scientific, technological and engineering breakthroughs. Cosmos is published by The Royal Institution of Australia, a charity dedicated to connecting people with the world of science. Financial contributions, however big or small, help us provide access to trusted science information at a time when the world needs it most. Please support us by making a donation or purchasing a subscription today.
