Male fertility is key for pregnancy. Many couples struggle to conceive because of low sperm count, known as oligospermia. This disease refers to a sample of semen that has less sperm than usual, usually less than 15 million sperm per milliliter. A low number of sperm can make it much harder to fertilize an egg, which lowers the chances of getting pregnant. It is one of the most common reasons men can’t have children, but it is often ignored. Many things can cause this, such as bad habits, health problems, genetics, and the surroundings. For successful treatment and long-term prevention, it’s essential to understand these root causes.