The reasons behind teen pregnancy arecomplex, varied, and overlapping. In fact,from a review of at least 250 studies,Emerging Answers culls more than 100 pre-cursors or "antecedents" to early teen sexualintercourse, poor contraceptive use, preg-nancy, and childbearing. These risk factorsfall under such categories as community dis-advantage; family structure and economicdisadvantage; family, peer, and partner atti-tudes and behavior; and characteristics ofteens themselves, including biology, detach-ment from school, other behaviors that putyoung people at risk, emotional distress, andsexual beliefs, attitudes, and skills. While allteens are at some risk, some teens are atmuch higher risk than others.