Smoking affects fertility

Smokers are more likely to have fertility problems than non-smokers. Smoking causes harmful chemicals to spread throughout entire body and all organs. This can lead to fertility problems. Due to the toxins from cigarettes, smokers are more likely to suffer from miscarriage than non-smokers. In addition, smoking increases several health risks during pregnancy, such as preterm labour and ectopic pregnancy.
Ovulation problems, Genetic issues, Damage to reproductive organs, Damage to eggs or premature menopause, Increased risk of cancer and increased risk of miscarriage.

Men that smoke cigarettes are at an increased risk for the following male fertility problems like lower sperm count and sperm motility problems (motility is the ability of sperm to swim towards and penetrate the egg)
Hormonal issues and erectile dysfunction also can occur in smokers.

Couples seeking treatment for fertility should stop smoking at least three months before attempting in vitro fertilization, because new sperms need at least that much time to be produced from germ cell to full maturity.