RESUMO
OBJECTIVE: To compare the obstetric outcomes and socio-demographic factors in electronic cigarette (EC) users with cigarette smokers and non-smokers in pregnancy. DESIGN: Prospective observational cohort study. SETTING: A large urban maternity hospital delivering almost 8500 infants per year. POPULATION: Pregnant women attending for antenatal care. METHODS: Electronic cigarette users at time of booking history were prospectively identified. Maternal and neonatal outcomes were compared with those of pregnant smokers and non-smokers. Multiple logistic regression analysis was performed to estimate the association between the explanatory variables and birthweight. MAIN OUTCOMES MEASURES: Infant birthweight, gestation at delivery, incidence of low birthweight. RESULTS: A total of 218 women with exclusive EC use and 195 women with dual use of both cigarettes and EC, had a live birth during the study period. EC users were of higher socio-economic status than smokers. Infants born to EC users had a mean birthweight of 3470 g (± 555 g), which was similar to that of non-smokers (3471 ± 504 g, P = 0.97) and significantly greater than that of smokers (3166 ± 502 g, P < 0.001). The mean birth centile of EC users was similar to non-smokers (51st centile versus 47th centile, P = 0.28) and significantly greater than that of smokers (27th centile, P < 0.001). Dual users had a mean birthweight and birth centile similar to that of smokers. CONCLUSION: The birthweight of infants born to EC users is similar to that of non-smokers, and significantly greater than cigarette smokers. Dual users of both cigarettes and EC have a birthweight similar to that of smokers. TWEETABLE EXTRACT: Birthweight of infants born to electronic cigarette users appears to be similar to that of non-smokers.
