Oligospermia It means less volume of sperm than normal. Proper volume of sperm is necessary for fertility. Cause Smoking is also the cause of oligospermia. When someone is addicted to it it can cause lung cancer but smoking also cause the atrophy of sexual glands. The main gland is prostate gland. The main function of it is to produce secretions that lubricate the reproductive tract as well as protect sperm from secondary defects ( the defects that are occurred during transportation of sperm through reproductive tract ) such as tail less, without tail, coiled tail etc Chemical agent Thus the chemical present in smoke agent cause the contractions of glands. The less secretary cells remains behind and it will produce less volume and the reproductive tract is less lubricate. Hence sperm are defective until reach into the female reproductive tract. Conclusion Smoking can cause infertility in male due to oligospermia