Smoking during pregnancy was up to 70% more common in the most deprived municipalities - a multilevel analysis of all singleton births during 2005-2010 in Finland.
OBJECTIVE
We investigated whether there was an association between maternal smoking habits during pregnancy and municipality level deprivation defined based on education, income and unemployment after adjustment for individual level covariates, including socioeconomic status (SES), in Finland, a Nordic welfare state.


METHODS
Data were gathered from the Medical Birth Register and comprised all singleton births (n=337,876) during 2005-2010. To account for any correlation of women clustered within a municipality, we fitted generalized estimating equation (GEE) models.


RESULTS
In total, 15.3% of the women with singleton pregnancies smoked during pregnancy. After adjustment for individual level confounders, smoking during pregnancy was 5.4-fold higher among women with the lowest as compared with highest individual SES. Controlling for individual SES, age and year of birth, women living in municipalities defined as intermediately and highly deprived based on education were 53.7% (adjusted odds ratio [aOR] 1.537, 95% confidence interval [CI] 1.493-1.583) and 71.5% (aOR 1.715, 95% CI 1.647-1.785), respectively, more likely to smoke during pregnancy than women in the least deprived municipalities.


CONCLUSIONS
Individual SES is the strongest correlate of smoking during pregnancy but conditional on individual variables; lower municipality aggregate education is associated with up to 70% higher smoking prevalence.
['Räisänen|Sari|S|', 'Kramer|Michael R|MR|', 'Gissler|Mika|M|', 'Saari|Juho|J|', 'Hakulinen-Viitanen|Tuovi|T|', 'Heinonen|Seppo|S|']
D000328:Adult D001294:Attitude to Health D015331:Cohort Studies D005260:Female D005387:Finland D006801:Humans D007231:Infant, Newborn D008423:Maternal Age D055361:Multilevel Analysis D011247:Pregnancy D011256:Pregnancy Outcome D012424:Rural Population D012907:Smoking D012923:Social Class D012959:Socioeconomic Factors
Smoking Pregnancy Multilevel analysis Socioeconomic status Childbirth Outcome Registries