Although the risks are obviously higher when you're pregnant, breastfeeding poses similar risks of illicit drug use for nursing moms and their babies as well. (romper.com)
The studies compared illicit drug use in the past year and rates of cannabis use disorder between states with and without medical marijuana laws. (businessinsider.com)
To put figures on illicit drug use, researchers routinely use surveys, supplemented by data from police and customs. (sciencemag.org)