Influence of smoking on fertility in women attending an in vitro fertilization program

Objective: To investigate the influence of cigarette smoking of women on the fertilization and pregnancy rates obtained by IVF treatment. Patients: One hundred ninety-seven infertile, otherwise healthy women who entered an NF program for the first time. Setting: Fertility unit at the Women's University hospital of the University of Ulm, Ulm, Germany. Interventions: The study population consisted of 197 women (23 to 39 years old) who were divided into the following groups: nonsmokers (n = 68), passive smokers (n = 26), and active smokers (n = 103) according to the cotinine concentration measured in follicular fluid. The reason for infertility was strictly a tubal factor with apparently normal ovulatory cycles. To guarantee an objective recording of tobacco smoke exposure, the smoking habit was not determined by questionnaires, but by cotinine, the principal metabolite of nicotine. Results: There were no significant differences in fertilization and pregnancy rates between the different groups. The E(2) serum levels were decreased significantly in women who smoked when compared with the results obtained from nonsmokers and passive smokers. Overall, a strong negative correlation of the cotinine and E(2) levels was observed (r = -0.65). Conclusion: The results suggest that there is no clinically detectable impairment of fertilization potential due to female smoking and that there is a greater influence on the outcome of IVF by other factors.