The effects of water-pipe smoking on birth weight: a population-based prospective cohort study in southern Iran

OBJECTIVES: Consecutive community health assessments revealed that water-pipe smoking in women and impaired growth in children were among the main health concerns in suburban communities in southern Iran. The aim of the present study was to identify the effects of water-pipe smoking during pregnancy on birth weight. METHODS: Data from a population-based prospective cohort study of 714 singleton live pregnancies in the suburbs of Bandar Abbas in southern Iran in 2016-2018 were used in this study. Data about water-pipe smoking patterns and birth weight were collected by questionnaires during and after the pregnancy. Low birth weight (LBW) was defined as a birth weight below 2,500 g. Statistical analyses were performed using generalized linear models, and the results were presented in terms of relative risk (RR) and 95% confidence intervals (CI). RESULTS: Fifty (8.2%) of the study subjects smoked water-pipe. The adjusted risk of LBW increased 2-fold in water-pipe smokers (adjusted RR [aRR], 2.09; 95% CI, 1.18 to 3.71), and by 2.0% for each 1-year increase in the duration of water-pipe smoking (aRR, 1.02; 95% CI, 0.99 to 1.05). CONCLUSIONS: Our results showed that water-pipe smoking during pregnancy was an important risk factor for LBW in this population sample from southern Iran. The introduction of regulations onto prevent water-pipe smoking and the implementation of community health action plans aiming at empowering women and increasing women’s knowledge and awareness regarding the health consequences of water-pipe smoking are proposed.