Association between cigarette smoking behavior and infertility in women: a case-control study

Introduction: The effects of smoking on decreasing the chance of fertility in women have been acknowledged but some aspects, such as smoking behavior, are currently unclear. The present study aims to evaluate the relationship between smoking traits and infertility in women through a comparative study with fertile women. Methods: This case-control study was conducted on 350 women (177 infertile and 173 fertile) in March-May 2014. Sampling was performed in two phases. Demographic and reproductive data were collected by questionnaires- for demographics and the Fagerstrom Test for Nicotine Dependence (FTND)). The total score of questionnaires was ten. The participants were divided into 3 groups: “Low Nicotine” dependency (0-4), “Moderate Nicotine” dependency (5) and “High Nicotine” dependency (6-10). To examine the relationship between smoking and infertility, both the chi-square test and logistic regression tests were used. Results: Tobacco use in infertile women was greater than that for fertile women (23.7% vs. 16.1%, respectively, P = 0.012); in fact, 16.7% of tobacco consumers had high nicotine dependency. Medium and low nicotine dependency were seen in 5.6% and 77.8% of tobacco consumers, respectively. Positive history of smoking increased the odds of being infertile (OR 2.88; 95% CI: 1.56- 4.92) and risk for infertility was associated with low nicotine dependency (OR 3.12; 95% CI 1.16-8.09). Conclusion: Low and high nicotine dependency increased the risk of infertility. Considering the physical, mental, social and economic effects of infertility in society, the negative effects of smoking on fertility should be considered and/or included in the training package for health service providers.