The many toxins in cigarettes, especially carbon monoxide, can damage the circulatory system making it difficult for blood to reach the penis which is necessary for erection. When you smoke tobacco hydrocarbons are inhaled damaging the lining of arteries and start forming plaques in their inner linings thus reducing blood flow. Nicotine constricts arteries to make them even narrower. When the arteries leading to a man's penis are blocked, he becomes impotent.
The toxins found in cigarettes can affect the testes, which is where sperm is produced. Smoking affects both semen and sperm, reducing their quality and affecting sperm mobility. Men who smoke also tend to have lower sperm counts than non-smokers and have more malformed sperm. This can make conception difficult and may also put a foetus at risk of developing from genetic material that has been damaged by smoking.
Consult Psychiatrist for nicotine de addiction..