Unplanned pregnancy in the extreme South of Brazil: prevalence, trends, and associated factors.

The study aims to estimate the proportion of puerperae with an unplanned pregnancy, evaluate trends and identify factors associated with its occurrence in Rio Grande-RS, Brazil. Trained interviewers applied a single, standardized questionnaire to all puerperae residing in the municipality in 2007, 2010, 2013, 2016 and 2019. The chi-square test compared proportions and the Poisson regression with robust variance adjustment in the multivariate analysis. The prevalence ratio (PR) was the effect measure employed. The study includes 12,415 puerperae (98% of the total). The unplanned pregnancy rate was 63.3% (95%CI: 62.5%-64.1%). After adjusting, the highest PR for not planning pregnancy were observed among younger, black women, living without a partner, with more significant household agglomeration, lower schooling, and household income, multiparous and smokers. The rate of unplanned pregnancy is high and stable, with a higher propensity among women those with the highest risk of unfavorable events during pregnancy and childbirth. Reaching these women in high schools, companies, services and health professionals, in addition to the mass media, can be strategies to prevent unplanned pregnancy.