Spatiotemporal heterogeneity of gestational syphilis in the 1st Health Region of Pará in the Brazilian Amazon.

Syphilis in pregnant women remains an important public health problem in Brazil, especially in urban contexts marked by social inequalities and weaknesses in the organization of health services. In the Amazon region, territorial, socioeconomic, and healthcare-related characteristics influence access to prenatal care, timely diagnosis, and the control of vertical transmission. Thus, this study aimed to analyze the spatiotemporal patterns of syphilis among pregnant women in a health region of the Brazilian Amazon. This is an ecological, descriptive, and quantitative study that evaluated 5,607 positive cases of syphilis in pregnant women residing in the 1st Health Region (Metropolitan I) of Pará, composed of Belém, Ananindeua, Marituba, Benevides, and Santa Bárbara, reported between 2019 and 2024. Data were obtained from the Pará State Health Department, and the "geocodebr" package from the National Institute for Space Research and the R software were used for georeferencing the geographic coordinates of each case. Kernel Density Estimation analysis identified the presence of high-density clusters in the 2019-2020 and 2023-2024 biennia. Spatial scan analysis identified Marituba as a significant cluster, indicating higher risk and a constant concentration of cases throughout the analyzed period. Syphilis in pregnant women presents a heterogeneous and persistent spatiotemporal pattern in the region, requiring integrated, territorialized, and intersectoral strategies.