Background/aim In Latin America and Caribe, the most common cause of mortality is hypertensive disorders in pregnancy (HDP). Some researchers found that air pollution increase the risk of HDP. However, the evidence regarding to preeclampsia has not been conclusive. In Temuco, PM2.5 exceeds daily and annual standards due to the use of wood as fuel. We aimed to estimate associations between preeclampsia and PM2.5.

Methods Temuco and Padre Las Casas are located in the south of Chile (39.7°E; 73.0°S). During the colds months increase the use of residential heating. PM2.5 was collected from 2009 to 2014 from Las Encinas air pollution monitoring station. Meteorological data (temperature (°C), wind speed (kn), relative humidity (%)) were obtained from the Chilean Meteorological Office. Reproductive data from pregnant women attending the Hospital were obtained from the databases compiled by the Obstetric Service. Data were descriptively analysed according to their distribution using mean, median, percentiles and their respective dispersion measure, depending on the variable distribution. We performed bivariate and multivariate analysis. We used STATA (version 13) to perform all the statistical analyses.

Results The prevalence of preeclampsia is 3.8%. Around 63.5% of cases are 20–34 years-old, 53.1% obese at last prenatal control, 6.7% has gestational or pregestational diabetes. We found differences between educational level, nutritional status, presence of maternal morbidities, multiple pregnancies (p<0.05). The mean concentration is 40.9 µg/m³. Exists differences in the seasonal time by hour of the day. From 6 pm to 4 am, the PM2.5 concentrations increase during the winter. The same is found during weekday or weekend (I am currently working on teh development of multivariate analysis).

Conclusion The results indicate that the prevalence of preeclampsia is high. Temuco has high PM2.5 concentrations, over the national standards, attributable to wood burning.