Oligozoospermia, refers to semen with a low sperm concentration or “sperm count is a common finding in male infertility. As defined by the World Health Organization (WHO) in 1999, a low sperm count is less than 20 million sperm/ml.
Causes of oligospermia include an obstruction of the normal flow of sperm due to such conditions as testicular trauma. Oligospermia may also result from scarring due to surgery on the male reproductive system or from infection .and sexually transmitted disease
A decrease in sperm production is another cause of oligospermia. This can be due to such conditions as varicoceles, hormonal disorders, diseases of the testicles, and obesity. Other causes of oligospermia include stress, smoking, drug or alcohol use, some medications, exposure to some toxins, malnutrition, and being underweight. Some sexually transmitted disease, such as Chlamydia, and gonorrhea can also result in oligospermia.