Cigarette smoking affects uterine receptiveness

Abstract
Cigarette smoking has long been known to have an effect on female fertility. The existence of an ovarian factor is clear when one considers that the mean age of the menopause is lower and IVF cycle outcome is worse in heavy smokers. The hypothesis of a concomitant uterine effect is raised by indirect evidence from in vitro and in vivo studies, but as yet, no direct evidence has been gained to confirm its existence. In this work, we analyse the association between smoking habit in oocyte recipients and cycle outcome. We have retrospectively analysed the outcome of all oocyte donation cycles performed in our clinic from January 2002 to June 2005 from which there was available information regarding patient current smoking status. Husband and donor smoking status were controlled variables, as well as donor and recipient age, patient body mass index, embryo number and quality and duration of endometrial priming. Pregnancy rate (PR) in non-heavy smokers (0-10 cigarettes/day) was significantly higher than in heavy smokers (>10 cigarettes/day) (52.2 versus 34.1%, respectively). Interestingly, multiple PR was significantly higher in heavy smokers (60 versus 31%). Tobacco consumption determines reduced uterine receptiveness and an increased risk of multiple pregnancies. This last issue remains to be clarified.