Tobacco Smoking, Coffee, Alcohol Abuse & Fertility
Tobacco smoking markedly affects the reproductive health of both men and women.
Heavy alcohol consumption indirectly affects the fertility when associated with nutritional or secondary health disorders.
In females, smoking is associated with a rapid decline of ovarian reserves, delayed conception and heightened risk of spontaneous miscarriage, as well as a lower success rate from ART, while in males the percentage of normal semen morphology and motility is significantly reduced.

The influence of alcohol intake on reproductive outcomes has already been investigated in several studies, yet it is still impossible to demonstrate a significant correlation between alcohol intake and oocyte maturation and fertilization in females, and between male alcohol consumption and the rate of lost pregnancies.
Firns and co-workers evaluated the impact of these lifestyle factors on in vitro fertilization (IVF) outcomes in 351 couples attending the PIVET Medical Center in Western Australia. Considering the quantity of collected oocytes, fertilization rates, pregnancy, and pregnancy loss, the multiple regression analysis showed that smoking strongly damages the quality of gametes in both sexes resulting in a reduction of ovarian reserve in women, and in a significant decrees in density, count, mobility and morphology of sperm in men.
On the contrary, female alcohol consumption did not show any correlation with fertility parameters, while in males it even showed a positive effect on fertilization rate, in the cohort with an associated consumption of fruit and vegetables. Therefore, based on the results of the Authors and the current literature, there is an important impact of tobacco smoking on IVF clinical outcomes, whereas a defined role of alcohol assumption needs to be still defined
Finally, evidence suggests that high intake of caffeine has a potential dose-response association resulting in both a longer time for conception and increased risk of pregnancy loss.
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