STUDY OBJECTIVE: To examine whether attitude to school is associated with subsequent risk of teenage pregnancy. To test two hypotheses that attitude to school is linked to pregnancy via pathways involving young people having "alternative" expectations or deficits in sexual health knowledge and confidence. DESIGN: Analysis of longitudinal data arising from a trial of sex education. Examination of associations between attitude to school and protected first sex, unprotected first sex, unprotected and protected last sex, and pregnancy, both crude and adjusting in turn for expectation of parenting by age 20, lack of expectation of education/training at age 20, and sexual health knowledge and confidence. SETTING: Schools in central and southern England. PARTICIPANTS: Girls of median age 13.7 years at baseline, 14.7 years at follow up 1, and 16.0 years at follow up 2. MAIN RESULTS: In unadjusted analysis, attitude to school was significantly associated with protected and unprotected first sex by follow up 1, protected first sex between follow up 1 and 2, unprotected last sex, and pregnancy. Dislike of school was more strongly associated with increased risk of these outcomes than was ambivalence to school. These associations remained after adjusting for socioeconomic status and for expectation of parenting, lack of expectation of education/training, and various indicators of knowledge and confidence about sexual health. CONCLUSIONS: Dislike of school is associated with subsequent increased risk of teenage pregnancy but the mechanism underlying any possible causal link is unlikely to involve "alternative" expectations or deficits in sexual health knowledge or confidence.