Mounting research points to health harms from cannabis, THC and CBD use during pregnancy, adolescence and other periods of rapid development

Marijuana use by the mother can affect a baby's brain development. John Fedele/Tetraimages via Getty Images

Cannabis is a widely used psychoactive drug worldwide, and its popularity is growing: The U.S. market for recreational cannabis sales could surpass US$72 billion by 2023.

As of early 2023, 21 U.S. states and the District of Columbia have legalized cannabis for recreational use for people age 21 and up, while 39 states plus the District of Columbia have legalized it for medical use.