On the basis of previous literature which indicated that individuals with either Conduct Disorder, Oppositional Defiant Disorder or ADHD show increased risky sexual behavior compared to controls, the aim of this studie was to investigate the prevalence of induced abortions among Danish girls diagnosed with ADHD and/or Conduct Disorder compared to a non-affected community control group from the same birth cohort. To investigate this, all Danish girls born between 1990 and 1996 and diagnosed with ADHD and/or Conduct Disorder based on the ICD-10 criteria in the age between 5 and 15 were matched by year of birth and sex to a random sample of participants without ADHD and Conduct Disorder using Danish national registers. All groups were followed at least until the age of 18. The Cox proportional hazard models were applied to estimate the risk of having an induced abortion if diagnosed with ADHD, Conduct Disorder or comorbid ADHD and Conduct Disorder before and after adjusting for other risk factors; other comorbid disorders, parental income and urbanization. Descriptive statistics revealed that the ADHD cohort was followed up at a mean of 20.1 (SD = 1.8) years; the Conduct Disorder cohort at a mean of 21.0 (SD = 1.9) years; the comorbid ADHD and Conduct Disorder cohort at a mean of 20.1 (SD = 1.8) years; and the control cohort at a mean of 19.7 (SD = 1.9) years. Based on n = 871 individuals with ADHD, n = 103 (11.8 %) have had at least one induced abortion; based on n = 749 individuals with Conduct Disorder, n = 142 (19 %) have had at least one induced abortion; based on n = 280 individuals with comorbid ADHD and Conduct Disorder, n = 56 (20 %) have had at least one induced abortion; and based on n = 6166 individuals in the control cohort, n = 309 (5 %) have had at least one induced abortion. The ADHD cohort had a mean age of 17.3 (SD = 2.3) at the first abortion; the Conduct Disorder cohort had a mean age of 17.7 (SD = 2.1); the comorbid ADHD and Conduct Disorder cohort had a mean age of 17.0 (SD = 2.1); and the control cohort had a mean age of 18.4 (SD = 2.2). Furthermore, the results from the Cox regression showed that both ADHD (HR = 2.78; 95 % CI = 2.22 – 3.48; p <0.001), Conduct Disorder (HR = 3.89; 95 % CI = 3.19 – 3.75; p <0.001) and comorbid ADHD and Conduct Disorder (HR = 4.98; 95 % CI = 3.74 – 6.62; p <0.001) were significantly associated with increased risk of having an induced abortion. Subsequent to the adjustment for various risk factors, ADHD (HR = 2.92; 95 % CI = 2.28 – 3.75; p <0.001), Conduct Disorder (HR = 3.52; 95 % CI = 2.84 – 4.37; p <0.001) and comorbid ADHD and Conduct Disorder (HR = 5.05; 95 % CI = 3.70 – 6.90; p <0.001). Low and middle parental incomes were also significantly associated with the risk of induced abortion while comorbidity with substance use disorder, major depression and personality disorder showed a tendency towards this. The discussion of the results suggested that the association between having either ADHD, Conduct Disorder or comorbid ADHD and Conduct Disorder and having an induced abortion can be due to different cognitive disabilities such as inattention, impulsivity and problems with working memory. It is further suggested that the increased risk of having either Conduct Disorder or comorbid ADHD and Conduct Disorder compared to having ADHD can, among other things, be explained by the fact that girls with Conduct Disorder are having more difficulties with judging the risk of their behavior compared to girls with ADHD. Finally, the impact of other risk factors was discussed, and we argue that, when trying to prevent pregnancies and induced abortions, a particular focus should be addressed to parental income, which is seen as a proxy for socioeconomic status. All things considered, the results indicate that individuals with either ADHD, Conduct Disorder or comorbid ADHD and Conduct Disorder have an increased risk of having an induced abortion compared to their controls after adjusting for other risk factors. Individuals with comorbid ADHD and Conduct Disorder have the biggest risk, followed by Conduct Disorder and ADHD respectively. The results also indicate that low and middle parental incomes increase the risk of having an induced abortion.