JAMA: Two studies published online by JAMA examine trends in marijuana use among pregnant and nonpregnant women of reproductive age, and use for medical purposes among adults in the United States. In one study, Deborah S. Hasin, Ph.D., Qiana L. Brown, Ph.D., M.P.H., L.C.S.W., of Columbia University, New York, and colleagues used data from women ages 18 through 44 years from the annual National Survey on Drug Use and Health from 2002 through 2014 to determine whether marijuana use has changed over time among pregnant and nonpregnant reproductive-aged women.
Between 2001 and 2013, marijuana use among U.S. adults more than
doubled, many states legalized marijuana use, and attitudes toward
marijuana became more permissive. In aggregated 2007-2012 data, 3.9
percent of pregnant women and 7.6 percent of nonpregnant
reproductive-aged women reported past-month marijuana use. Although the
evidence is mixed, human and animal studies suggest that prenatal
marijuana exposure may be associated with poor offspring outcomes (e.g.,
low birth weight, impaired neurodevelopment). The American College of
Obstetricians and Gynecologists recommends that pregnant women and women
contemplating pregnancy be screened for and discouraged from using
marijuana and other substances.
Of the 200,510 women analyzed, 29.5 percent were ages 18 through 25
years and 70.5 percent were ages 26 through 44 years; 5.3 percent (n =
10,587) were pregnant. Among all pregnant women, the prevalence of
past-month marijuana use increased from 2.4 percent in 2002 to 3.9
percent in 2014, an increase of 62 percent. The prevalence of past-month
marijuana use was highest among those ages 18 to 25 years, reaching 7.5
percent in 2014, significantly higher than among those ages 26 to 44
years (2.1 percent). However, increases over time did not differ by age.
Past-year use was higher overall, reaching 11.6 percent in 2014, with
similar trends over time. In nonpregnant women, prevalences of
past-month use (2014: 9.3 percent) and past-year use (2014: 16 percent)
were higher overall, with similar trends over time. Increases over time
in past-month marijuana use did not differ by pregnancy status.
“These results offer an important step toward understanding trends in
marijuana use among women of reproductive age. Although the prevalence
of past-month use among pregnant women (3.85 percent) is not high, the
increases over time and potential adverse consequences of prenatal
marijuana exposure suggest further monitoring and research are
warranted. To ensure optimal maternal and child health, practitioners
should screen and counsel pregnant women and women contemplating
pregnancy about prenatal marijuana use,” the authors write.
(doi:10.1001/jama.2016.17383; the study is available pre-embargo at the For the Media website)
Editor’s Note: This work was supported by
grants from the National Institute on Drug Abuse and the New York State
Psychiatric Institute. All authors have completed and submitted the
ICMJE Form for Disclosure of Potential Conflicts of Interest and none
In another study, Wilson M. Compton, M.D., M.P.E., of the National
Institute on Drug Abuse, Bethesda, Md., and colleagues examined
differences between medical and nonmedical marijuana users across all
By 2014, 23 states and the District of Columbia had legalized medical
marijuana use, suggesting a need for information about national rates
of marijuana use for medical purposes. Although 17 percent of past-year
marijuana users reported use for medical purposes in states with medical
marijuana legalization, physicians might recommend medical marijuana
use to patients regardless of their residing states.
For this study, the researchers used data from adults 18 years and
older who participated in the 2013-2014 National Survey on Drug Use and
Health, which provides representative data on marijuana and other
substance use among the U.S. population. Based on 96,100 respondents, 13
percent of U.S. adults had past-year marijuana use (nonmedical use
only, 12 percent, medical use only, 0.8 percent, combined use, 0.5
percent). Among past-year adult marijuana users, 90 percent used
nonmedically only, 6.2 percent used medically only, and 3.6 percent used
medically and nonmedically. Of medical marijuana users, 79 percent
resided in states where medical marijuana was legal, and 21 percent
resided in other states.
“Using nationally representative data, 9.8 percent of adult marijuana
users in the United States reported use for medical purposes. Although
the prevalence of medical use was higher in states that had legalized
medical marijuana, 21.2 percent of medical marijuana users resided in
states that had not, suggesting physicians might recommend medical
marijuana use regardless of legalization,” the authors write.
“Similarities in correlates of medical and nonmedical users,
especially co-occurrence with psychiatric conditions and other substance
use, suggest that some marijuana users may access medical marijuana
without medical need. However, medical-only marijuana users differed
from nonmedical-only users in ways that are consistent with use to
address medical problems.”
(doi:10.1001/jama.2016.18900; the study is available pre-embargo at the For the Media website)
Editor’s Note: Please see the article for
additional information, including other authors, author contributions
and affiliations, financial disclosures, funding and support, etc.