This research examined adolescent males’ decision-making when confronted with a hypothetical unplanned pregnancy in a sexual partner. An innovative methodology, involving a computerized simulation game was utilized with 386 Australian males (mean age of 15 years). Data were gathered from responses made during the simulation, and questionnaires assessed idealization of pregnancy and parenthood, stereotypic male beliefs and self-esteem. Descriptive findings are presented, together with multivariate analyses to examine predictors of participants’ choices about whether to (a) terminate the pregnancy and (b) continue the relationship with the sexual partner. Idealized beliefs about pregnancy and parenthood were important in the decision relating to the pregnancy outcome (p < 0.001). The computer simulation has potential as a cost-effective component of adolescent pregnancy prevention programs that could challenge these idealized beliefs.