A growing number of pregnant women are using marijuana, and the habit is expanding fastest among teens and young adults, a USA study suggests. Researchers found that marijuana consumption among pregnant women in the state has risen from 2009 to 2016 from 4.2 percent to 7.1 percent.
More than one-fifth of American teenagers are using marijuana during pregnancy, a new study finds.
The Journal of the American Medical Association, known as JAMA, published on December 26, a research letter on data analysis that indicates cannabis use is increasing among pregnant women, and particularly for young mothers. Last year, 5.1 percent of women between the ages of 25 and 34 years old reported to using marijuana while pregnant, up from 3.4 percent in 2009.
Researchers relied on self-administered questionnaires completed by 279,457 women eight weeks into their pregnancy.
However, the study notes that some of the patients who did not say they used marijuana on their questionnaires, later tested positive on a cannabis toxicology test, leading researchers to state their data was "likely" underreported.
Media reports noted that the time span of the study coincides with increased marijuana legalization in California, and the US, and may be indicative of a continuing trend, as recreational legalization in California is scheduled to take effect on January 1.
The proportion of women there who used marijuana in some form while they were pregnant almost doubled between 2009 and 2016.
Experts believe that the use of marijuana could potentially harm a fetus's brain development, cognition and birth weight, The New York Times noted, and its main psychoactive ingredient, tetrahydrocannabinol (THC), could be transferred to a baby via breast milk.
"Think about marijuana use from [the study participants'] perspective, especially in Northern California", said Dr. Robyn Horsager-Boehrer, a professor of obstetrics and gynecology at the University of Texas, who was not involved in the study. As of January 1, recreational marijuana will be legal in the state for people over 21. A total of 23 states have laws that allow the use of marijuana for medicinal purposes to some extent.