Because of their association with serious health consequences and addiction, marijuana/hashish, cocaine, inhalants, hallucinogens, crack, and prescription-type psychotherapeutic drugs used for non-medical purposes are classified as illicit drugs. In 2003, a total of 12.5 million women (11.3 percent) aged 18 or older reported using an illicit drug within the past year. The past-year illicit drug use rate is significantly higher among women aged 18-25 than among women over age 25 (30.5 percent compared to 8.1 percent). Among adolescent females (aged 12-17), 21.9 percent reported using illicit drugs in the past year. When stratified by race, the rate of illicit drug use among adolescent females was more common among non-Hispanic Whites (23.4 percent) than Hispanics (21.8 percent) or non-Hispanic Blacks (18.2 percent).

In 2003, marijuana was the illicit drug most commonly used by females in all age groups. Among females, those aged 18-25 had the highest rate of past year marijuana use (24.0 percent), though the rate of marijuana use in this age group declined from 2002 to 2003. The second most common type of illicit drugs used in the past year by women aged 18-25 was prescription-type psychotherapeutic drugs used for non-medical purposes—these were used by 13.5 percent of women aged 18-25 years. Adolescent females’ drug use patterns differed from those of adult women. Those aged 12-17 reported the highest rate of inhalant use compared to their older counterparts.

In 2002 and 2003, 4.3 percent of pregnant women aged 15 to 44 years reported using illicit drugs in the month prior to their survey interview. Among the subgroup of 15- to 17-year-old pregnant youth, approximately one of eight, or 12.8 percent, reported illicit drug use in the past month. At the same time, it is important to note that the past-month illicit drug use rate was much lower among pregnant women than among non-pregnant women in all age groups.

Graph: Females Reporting Past Year Use of Illicit Drugs, by Age and Drug Type[d]