Does environmental cigarette smoke affect breastfeeding behavior?

BACKGROUND: Exposure of lactating women to environmental cigarette smoke may increase cotinine in breast milk, which in turn may reduce the volume of milk and the duration of breastfeeding. OBJECTIVES: To assess the relationship between exposure to environmental cigarette smoke and breastfeeding behavior. MATERIALS AND METHODS: This prospective cohort study was conducted on 290 mothers in Babol - Iran, who had been breastfeeding for 3–5 days after delivery. The lactating mothers were divided into two groups: those exposed to environmental cigarette smoke, and those free from smoke exposure. The study questionnaire included demographic data, information on environmental cigarette smoke, and breastfeeding behavior. Data was collected through telephone interviews at 2, 4, and 6 months of follow-up. Statistical analysis included descriptive statistics, and test of significance using Chi-square test, t-test, log-rank test, and Cox proportional hazards model. RESULTS: The continuation of breastfeeding for the group of exposed mothers and the unexposed group was (mean ± standard deviation) 5.57 ± 0.098 and 5.58 ± 0.109, respectively in 6 months of follow-up. There was no significant difference between the two groups (P = 0.93). The percentage of exclusive breastfeeding at 6 months in the group exposed to cigarette smoke was 65% compared to 76% of the nonexposed group. However, the difference was not statistically significant (P = 0.149). CONCLUSIONS: In this study, no significant association was observed between the group exposed to environmental cigarette smoke and the nonexposed group in breastfeeding behavior, although the percentage of exclusive breastfeeding at 6 months was less in the group exposed to environmental cigarette smoke. Further exploratory studies are needed.