OBJECTIVE: To provide a baseline estimate of the national prevalence of pregnancy-related illicit drug use and abstinence rates.
METHODS: We analyzed data collected between 1996 and 1998 from the National Household Survey on Drug Abuse, a nationally representative sample survey of 22,303 noninstitutionalized women aged 18-44 years, of whom 1249 were pregnant.
RESULTS: During 1996-1998, 6.4% of nonpregnant women of childbearing age and 2.8% of pregnant women reported that they used illicit drugs. Of the women who used drugs, the relative proportion of women who abstained from illicit drugs after recognition of pregnancy increased from 28% during the first trimester of pregnancy to 93% by the third trimester. However, because of postpregnancy relapse, the net pregnancy-related reduction in illicit drug use at postpartum was only 24%. Marijuana accounted for three-fourths of illicit drug use, and cocaine accounted for one-tenth of illicit drug use. Of those who used illicit drugs, over half of pregnant and two-thirds of nonpregnant women also used cigarettes and alcohol. Among the sociodemographic subgroups, pregnant and nonpregnant women who were young (18-30 years) or unmarried, and pregnant women with less than high school education had the highest rates of illicit drug use.
CONCLUSION: The continued burden of illicit drug use during pregnancy calls for policy efforts to enable primary care providers to identify and refer women who use substances to treatment and support services. Prevention of uptake of illicit drug use should be an integral part of public health programs for young women.
Illicit drug use is the ninth leading contributing cause of death in the United States.1 The public health concern about substance use during pregnancy is reflected in the statement by the US Senate Committee on Appropriations in 1991, which called for monitoring its trends and adverse effects.2 Although the evidence about the adverse effects of prenatal illicit drug use on pregnancy and childhood have been inconsistent, with some studies showing an association between illicit drug use and adverse maternal and child health outcomes and other studies showing no such association,3-7 prenatal illicit drug use is a topic that has evoked multifaceted legal and political controversies.7,8 The role of illicit drug use in the transmission of human immunodeficiency virus (HIV) remains most clearly appreciated. Clearly, illicit drug use is associated with increased morbidity and mortality and also predisposes women who use illicit drugs to other risk factors that are harmful to the women and their pregnancies including violence and transmission of HIV, hepatitis B and hepatitis C viruses, and other sexually transmitted infections.1,9-12
Baseline data on the burden of prenatal substance use is needed to monitor progress towards the Year 2010 national objective on substance abuse reduction by pregnant women (ie, to increase abstinence from illicit drugs during pregnancy to 100%).13 Surveillance of illicit drug use is difficult. Urine toxicology screens are expensive and are sensitive only in a specific time frame. Use of hair for assessment of drug use is limited by the fact that coarse black hair incorporates more of the drug than brown or blond hair, necessitating the need for differential scaling by hair color. Both the hospital discharge data and birth certificate-based data on substance use are subject to bias in data collection and reporting. Therefore, self-report surveys remain a rational choice for surveillance of prenatal drug exposure. From 1994 on, the National Household Survey on Drug Abuse included questions on pregnancy status for childbearing-aged women.14 The National Household Survey on Drug Abuse is the only national survey that allows assessment of substance use behaviors by trimester of pregnancy.
In this study, we used the National Household Survey on Drug Abuse data to estimate the prevalence of illicit drug use and pregnancy-related abstinence from illicit drug use and its correlates among women of childbearing age in the United States from 1996 through 1998. Because illicit drug use is often associated with use of other substances, we included data on other substances such as tobacco and alcohol.