Any intervention to reduce repeat unintended pregnancies in teenagers or encourage teenage mothers to delay further pregnancies (birth spacing). Such interventions may be population-based strategies or policies, or single strategy interventions targeting specific groups; for example, contraception advice or provision, or interventions with a multifaceted strategy that could include a combination of school- and community-based or targeted efforts. These interventions may, for example, be nurse-led interventions, or occur in a group setting that includes peer-support. Building blocks of these interventions could include, in differing combinations: elements of health education, skills building, contraception education and distribution, individual counselling, etc.