In upto 40% of infertile couples, the male plays a key a role for difficulty in conception. Infertility means failure to conceive after regular unprotected intercourse for one year.
According to WHO (2002), approximately one third of the world's male adult population smoke. Smoking exposes the spermatozoa to oxidative agents. 68% of smokers showed oligospermia and 63% showed asthenozoospermia. Tobacco contains some deadly toxic carcinogens, nicotine, carbon monoxide, nitrogen oxide and cadmium, which negatively affect male and female gametes and embryo. Tobacco chewing, which is very common in India, affects sperm parameters. Tobacco contains 30 mutagenic agents, of which nicotine is the most hazardous. It gets absorbed through skin, mucous membrane & respiratory tract and gets metabolised in the liver. The metabolised products get deposited in the semen, saliva, milk and seminal plasma which affect the sperm plasma membrane, causing infertility by their powerful oxidising action.
Alcohol consumption decreases the spermatogenesis, interferes with the production of GnRH, FTH, LH and testosterone. It also impairs the function of leydig cells and sertoli cells in the testes. Oligoseprmia is much higher in alcoholics.