Oligospermia is the term for low sperm count in men. According to World Health Organization (WHO) sperm parameters published since 2010, a sperm count below 15 million is considered oligospermia. Oligospermia, or low sperm count, is a significant cause of male infertility. Factors such as varicocele, various infections, and exposure to chemicals can cause oligospermia, and treatment is planned according to the underlying cause.