[What are the epidemiological data on maternal and paternal smoking?]

A review of the literature published over the last fifteen years shows that active smoking (1.54 [95% CI 1.19-2.01]) and passive smoking (1.17 [95% CI1.02-1.37]) are the cause of a decline in female fertility in the general population. This lower fertility is particularly evident for in vitro fecundation where the relative risk of infertility measured in one study was 2.41 (95% CI 1.07-5.45) and even 4.27 (95% CI 1.53-11.97) if the couple has smoked for five years. Paternal smoking at the time of IVF decreases the number of ovocytes by 46% due to maternal passive smoking. The risk of not having a live infant is high: 3.76 (95% CI 1.40-10.03, p < 0.01). In the general population, active smoking increases the risk of spontaneous abortion by 60-100%, depending on the intensity of smoking. The latest report published in France shows that 37% of women declare they smoked before pregnancy. This rate decreased to 17% during the first trimester, 15% during the second and 14% during the third then rose again to 20.5% two years after delivery. About half of the women who stopped smoking during pregnancy start again after delivery. The desire to breastfeed is lower among smokers, and fewer start breastfeeding which is continued for a shorter time. The effect of paternal smoking has not been described for this factor in France.