Background: Low birth weight is a high indicator in developing countries that has been associated with several short- and long-term consequences; maternal factors associated with it have been identified. Objective: The objective of this research was to determine the maternal factors associated with low birth weight in the Loreto region 2017-2021. Materials and methods: A descriptive, cross-sectional, retrospective and correlational study was carried out, which included all the patients who met the inclusion criteria of the "Microdata" database, which are the data collected through the Demographic and Family Health Survey (ENDES) carried out by the National Institute of Statistics and Informatics (INEI). Maternal-neonatal, maternal sociodemographic and health services factors were associated. Results: 2139 births were analyzed: 1876 (87.7%) births with normal weight, 238 (11.1%) with low ...