Infants born with a birth weight below 2,500 grams are at significant risk of mortality and morbidity. A higher proportion of low birth weight infants is born to adolescents, who are themselves at higher risk of poverty, ill health, and diminished future opportunities. Therefore, improving or preventing low birth weight in this population is an important public health issue. The Low Birth Weight Review Group conducted a systematic review of the literature to determine the effectiveness of public health and health promotion strategies to reduce or prevent low birth weight in infants born to adolescents.A group of seven public health researchers, managers, and educators was formed to determine the research question, inclusion criteria, and to identify key contacts for primary research. The sources included electronic databases (English and French language), hand searches of key public health and clinical journals and conference proceedings, bibliographies of all studies deemed relevant and contact of key informants to request published and unpublished studies. Two group members independently reviewed all abstracts of identified articles. All studies deemed relevant by either reviewer were marked for retrieval. Two raters independently assessed all retrieved studies for relevance and quality using previously developed tools.Raters resolved disagreements by discussion. Strong and moderate quality studies received data extraction.The raters identified 425 articles as being potentially relevant. Within the period set for this review, 372 (87.5%) of the articles were retrieved. A total of 16 published reports of 15 research studies were identified as relevant, of which four were assessed as methodologically strong, nine as moderate, and two as weak. Only two studies clearly based the intervention on atheoretical framework. Interventions were most often targeted to individuals (n=8), although some were also directed to families (n=4), and to groups (n=4). Health information (n=8) and strategies such as peer support (n=6) were used in the majority of studies. Five studies showed a statistically significant effect on birth weight. Home-delivered and clinic-delivered interventions are effective. Interventions using a combination of multiple strategies are more effective than those using a single strategy. It is difficult to attribute the effect on low birth weight to any single strategy because some studies used multiple strategies. Interventions that enrolled adolescents earlier in pregnancy are more effective then interventions that enrolled adolescents later in pregnancy. There appears to be some need for distinguishing between what works with pregnant adolescents and what works with older pregnant women.Public health professionals are positioned to provide or coordinate the multiple interventions deemed effective, such as home visiting and prenatal classes, in an organized, seamless fashion. New research should focus on well-designed prospective cohorts or randomized clinical trials that target adolescents specifically. Researchers should design studies to determine whether a combination of specific intervention strategies or individual strategies contributes to positive outcomes. Finally, a well-designed qualitative study could answer important questions about adolescents who have given birth to a low birth weight infant regarding their experiences of managing pregnancy, and their perception of what they think would have helped them to give birth to a normal-weight infant.