The underlying cause of oligospermia must first be investigated. For example, it is necessary to investigate whether the individual is exposed to chemicals, is overweight, has varicocele, or if the condition is idiopathic. Treatment is implemented after the underlying cause is determined. If oligospermia is present without an underlying cause, in-vitro fertilization (IVF) should be considered, or alternative assisted reproductive techniques may be preferred. For example, IVF is directly recommended for patients with sperm counts below 5 million. If the patient is overweight, they are referred to the Nutrition and Dietetics Department to lose weight, and may be supported by medication from an endocrinologist if necessary, or referred for bariatric surgery. If the individual has varicocele, surgery may be an option; post-surgery sperm count is monitored, and if improvement is seen, recovery is achieved. If there is no improvement, IVF is again considered. Individuals are advised to quit smoking and alcohol. However, if the level of oligospermia is severe, even these lifestyle changes may not significantly increase sperm count. IVF is generally recommended. Therefore, the patient's condition is important. In addition, parameters that vary from person to person, such as how long they have been married and the age of the patient's partner, are also considered.