Trend and disparities for smoking during pregnancy in the extreme south of Brazil between 2007 and 2019.

Abstract

Objective: To estimate the prevalence and to evaluate trends and disparities in the occurrence of smoking among pregnant women living in the municipality of Rio Grande (RS), in the extreme south of Brazil, between 2007 and 2019.

Methods: All pregnant women living in this municipality who had a child in one of the local hospitals between January 1st and December 31st in the years 2007, 2010, 2013, 2016, and 2019 were included in the study. The interviews took place within 48 hours after childbirth. A pregnant woman was considered a smoker if she smoked at least one cigarette per day for 30 consecutive days in any of the pregnancy trimesters. The respective Pearson's χ2 test was used to estimate the proportions and the trend.

Results: The mean prevalence of smoking in the studied period was 17.7% (95%CI 17.0-18.3), dropping from 23.4 (95%CI 21.7-25.0) in 2007 to 12.4% (95%CI 11.1-13.9) in 2019. This decrease occurred in all categories of the studied variables (p>0.001). The greatest disparities in the decrease were observed between the extreme groups for income (75.0 versus 34.4%) and level of education (51.0 versus 32.1%) and living or not with a partner (50.7 versus 27.7%).

Conclusion: There was a sharp and uneven drop in the prevalence of smoking over these 13 years. Pregnant women at higher risk of complications during pregnancy and childbirth were at a clear disadvantage compared to others. Reducing the prevalence of smoking depends on prioritizing interventions among pregnant women with greater social vulnerability.