Reardon, D. C., Coleman, P. K., & Cougle, J. (2004). Substance Use Associated with Unintended Pregnancy Outcomes in the National Longitudinal Survey of Youth. American Journal of Drug and Alcohol Abuse, 26, 369-383.

Abortion is known to be associated with higher rates of substance abuse, but no studies have compared substance use rates associated with abortion compared to delivery of an unintended pregnancy. This study examines data for women in the National Longitudinal Survey of Youth whose first pregnancy was unintended. Women with no pregnancies were also used as a control group. Use of alcohol, marijuana, cocaine, and behaviors suggestive of alcohol abuse were examined an average of four years after the target pregnancy among women with prior histories of delivering an unintended pregnancy (n = 535), abortion (n = 213), or those who reported no pregnancies (n = 1144). Controls were instituted for age, race, marital status, income, education, and prepregnancy self‐esteem and locus of control. Compared to women who carried an unintended first pregnancy to term, those who aborted were significantly more likely to report use of marijuana (odds ratio: 2.0), with the difference in these two groups approaching significance relative to the use of cocaine (odds ratio: 2.49). Women with a history of abortion also reported more frequent drinking than those with a history of unintended birth. With the exception of less frequent drinking, the unintended birth group was not significantly different from the no pregnancy group. Resolution of an unintended pregnancy by abortion was associated with significantly higher rates of subsequent substance use compared to delivering an unintended pregnancy. A history of abortion may be a useful marker for identifying women in need of counseling for substance use.

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