Telephone monitoring service for pregnant women and impact on prevalence of prematurity and associated risk factors in Piracicaba, Sao Paulo State, Brazil

This study aims to assess the impact of a telephone monitoring service on prevalence of prematurity and to analyze associated risk factors using data on 2,739 pregnant women. Estimation was based on hierarchical multiple logistic regression, with p = 0.05 for variables to remain in the model. Prevalence of preterm birth was 8.34% in monitored pregnant women and 10.18% in unmonitored women (p = 0.0058). Prevalence of preterm birth was inversely proportional to the number of monitoring calls (p < 0.0001). Variables associated with prematurity were maternal age < 19 years, history of death of two or more children, multiple pregnancy, diabetes, hypertension, fewer monitoring calls, extended standing or lifting heavy weights at work, smoking, fewer prenatal visits, no ultrasound examination, gestational diabetes, multiple pregnancy, and fetal abnormality. This low-cost strategy proved effective for reducing the preterm birth rate.