Background/aim: This study determined the effects of cotinine concentrations in follicular fluid (FF) and seminal plasma (SP) on the pregnancy outcome of couples using assisted reproductive techniques (ARTs). Materials and methods: This study was conducted as a case-control study. A total of 217 couples were included in the study. Among these couples, there were nonsmokers (66 women and 40 men), passive smokers (106 women and 54 men), and active smokers (45 women and 123 men). Demographic and smoking data were collected by questionnaire at the onset of treatment. FF and SP samples were obtained from the couples on the day of oocyte retrieval. Results: The cotinine concentrations in the FF and SP of nonsmokers were significantly lower than they were in the other groups (P = 0.001). The difference in cotinine concentrations detected in FF between women with positive pregnancy test results and women with negative pregnancy test results was statistically insignificant. It was also determined that the percentage of clinical pregnancy was lower in nonsmoker women than in passive smoker or smoker women (P > 0.05). Conclusion: Although we found there was no significant difference in the pregnancy outcome between nonsmoker and passive smoker or smoker women, smoking cessation should be an integral part of ARTs.