Does cigarette smoking really have detrimental effects on outcomes of IVF?

Cigarette smoke contains many toxic chemicals associated with poor reproductive outcome and reduced fertility. It also has a negative effect on sperm motility and morphology. The aim of this study was to analyze the effects of male and female cigarette smoking on the outcomes of in vitro fertilization (IVF).

In this comparative prospective analysis, the effects of smoking on outcomes of IVF including semen parameters, oocyte quality, fertilization rate, transfer day embryo scores and pregnancy rates were analyzed. For this purpose, patients were grouped based on their follicular or seminal fluid cotinine (a nicotine metabolite) levels as smokers and non-smokers (non-smokers: female (n=171), male (n=118), smokers: female (n=43), male (n=96)).

The mean age and baseline hormonal levels of all groups were found to be comparable. While the numbers of total and mature oocytes collected were higher in the smoker group (p=0.005 and p=0.006, respectively), oocyte quality index, fertilization rate, embryo development rate and pregnancy rate were not significantly different between the groups (p>0.05). Analysis based on the type of ovarian hyperstimulation protocol (GnRH agonist, antagonist and others) showed that within the antagonist group the mean age of smokers was significantly lower and the total number of collected oocytes was significantly higher compared with non-smokers. Cigarette smoking among men did not have a significant negative effect on outcomes of IVF whether their partners were smokers or nonsmokers. Regression analysis did not give any significant difference when male and/or female smoking status was analyzed for fertilization rates, transferred embryo qualities and clinical pregnancy rates.

Cigarette smoking does not have detrimental effects on outcomes of IVF.