Low birth weight is a world health problem that has a great impact on neonatal and infant mortality. In order to identify the factors associated with low birth weight in the municipality of Cárdenas, Cuba, an observational, analytical, epidemiological, case-control study was carried out. We worked with the total number of low birth weight live births in the municipality of Cárdenas during the year 2022. The short inter-gestational period variable was statistically significant and anemia, hypertensive disease during pregnancy, as well as inadequate weight gain were significant as risk factors. Low birth weight is the result of several events related to the pregnant woman before and after conception. Identifying the factors associated with low birth weight in pregnant women would reduce neonatal morbidity and mortality.