A home visit intervention program for adolescents throughout their pregnancy and during the early stages of motherhood was evaluated. The participants (N = 90) were part of a larger group of adolescents treated in two health centers in a poor neighborhood in Santiago, Chile. The program was carried out by volunteer community health monitors and evaluated through an experimental, randomized, controlled clinical trial. Cost-effectiveness was examined in comparison with standard health care. Results show higher scores for the intervention group on the mothers’ mental health and nutritional state, as well as on the children’s levels of linguistic development.