Introduction: Adolescent pregnancy causes serious problems not only for girls, but also for their family, and society. This study aimed to understand factors related to adolescent pregnancy in low- and middle-income countries using a multilevel approach adopted by Bronfenbrenner's ecological model. Methods: A total of 11,933 studies published in between 2000 and 2015 were identified in 4 databases. Based on inclusion criteria and risk of bias assessment, a total of 67 articles were retrieved for analysis. Results: Thematic analysis revealed that early marriage, sexual risk behaviors, substance use, family experience of adolescent birth, peer pressure, and lack of sex education and health service increased the hazards of adolescent pregnancy. Communication with parents, school activities, community meetings, laws, and government policies protected adolescents from pregnancy. Conclusions: Results of this study suggests that the background of adolescents and complex interactions among various factors should be considered for pregnancy. In future research, mixed-method that supplements the methodological weaknesses of previous studies is also recommended.
- Adolescent birth
- Adolescent pregnancy
- Low and middle-income countries
- Risk and protective factors
- Systematic review