Data from the 1993 Ohio (US) Youth Risk Behavior Survey were used to determine whether teenage girls with a history of pregnancy were more likely than their sexually active counterparts who did not become pregnant to engage in other problem behaviors. 592 (46.3%) of the 1280 female respondents recruited from Ohio public and private high schools (median age, 16.2 years) were sexually active and 98 (7.7%) had been pregnant. Logistic regression analysis, adjusted for the effects of the other variables in the model, confirmed that girls who had been pregnant differed significantly from their sexually active counterparts who did not become pregnant in terms of several recent risk behaviors, age of onset of behavior, and general behavior. Sexually active teens who carried a weapon in the 30 days preceding the survey were 4.06 times (95% confidence interval (CI), 1.75-9.42) more likely to have been pregnant than sexually active teens who had not carried a weapon. The pregnancy risk was 4.88 times greater (95% CI, 1.40-16.95) among sexually active girls who had ever used cocaine compared with never users and the pregnancy risk increased 1.43 times (95% CI, 1.14-1.80) for each additional year of substance abuse. Alcohol use in the past 30 days, on the other hand, was less likely to be associated with pregnancy (odds ratio, 0.37; 95% CI, 0.18-0.76). The pregnancy risk increased 1.75 times (95% CI, 1.26-2.43) for each additional sexual partner during the previous 3 months. For each year following initiation of sexual activity, the risk of pregnancy increased 1.43 (95% CI, 1.14-1.80). Finally, history of a sexually transmitted disease increased the risk by 3.50 times (95% CI, 1.28-9.55). Although the cross-sectional nature of this study precludes assessment of causality and the sample was biased toward in-school youth, the findings suggest a need to address multiple risk factors for adolescent pregnancy.