Maternal cannabis use during pregnancy may increase odds of autism

Children of mothers who use cannabis during pregnancy may have increased odds of developing autism spectrum disorders (ASD), according to a new study from Canada. 

Using data from a birth registry and health administrative databases, Daniel Corsi and colleagues reviewed information on births in Ontario between April 1, 2007 and March 31, 2012, before recreational cannabis was legalized. Of the half million women for whom data was available, 0.6% reported using cannabis while pregnant. 

The researchers found that the incidence of autism in these women’s children was 4.00 per 1,000 person-years, compared to 2.42 for unexposed children. When they looked specifically at data for women who used cannabis and no other substances such as cigarettes, alcohol, or tobacco, the risk remained elevated. In addition, the researchers say, “The incidence of intellectual disability and learning disorders was higher among offspring of mothers who used cannabis in pregnancy, although less statistically robust.” 

In earlier research, Corsi and colleagues found that cannabis use during pregnancy was linked to an increased risk of preterm birth.

Citations

“Maternal cannabis use in pregnancy and child neurodevelopmental outcomes,” Daniel J. Corsi, Jessy Donelle, Ewa Sucha, Steven Hawken, Helen Hsu, Darine El-Chaâr, Lise Bisnaire, Deshayne Fell, Shi Wu Wen, and Mark Walker, Nature Medicine, August 10, 2020 (online). Address: Daniel Corsi, [email protected]. 

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“Cannabis use in pregnancy linked to a greater risk of autism,” news release, The Ottawa Hospital, August 10, 2020