We present the evaluation of the population impact of a social and health maternal and child intervention, implemented in a low income urban area (Ciutat Vella) in Barcelona, Spain. Intervention was based on increasing access to health and social services for pregnant women and for the children. A quasiexperimental design with a nonequivalent control group and multiple measurements was used. We compared infant and perinatal cumulative mortality rates between Ciutat Vella District and the rest of the city, before (1983-86) and after the intervention (1987-89, 1990-92). Results showed that the significant differences found previously to the program between the mortality rates disappeared with the development of the program. Infant mortality in Ciutat Vella was 17.7/.000 births in 1983-86, and became 13.1/1.000 births in 1987-89, and 13.4 in 1990-92; in the rest of the city, infant mortality was 9.5/1.000 births in 1983-86, and became 8.8/ and 7.7/1000 births respectively. A comprehensive social and health care program implemented in small low income areas may contribute to reduce inequalities in maternal and child health.