The most common male fertility disorders are related to low sperm count, poor sperm quality, or even both. Any of the following can cause a man to have a decreased number of sperm or abnormal sperm:

• Varicocele — are swollen veins in the scrotum. It harms sperm normal development by blocking a proper blood drainage.
• Undescended testicles (when one or both testicles have not descended into the scrotum).
• Sexually transmitted infections, urinary tract infections or infections that cause fever.
• Genetic abnormalities (congenital chromosome disorders such as Klinefelter's syndrome and other genetic syndromes, associated with infertility include cystic fibrosis (mucoviscidosis), Kallmann's syndrome and Kartagener's syndrome and Y- chromosome microdeletion).
• Hormonal problems (disorders in the hypothalamus-pituitary endocrine system).
• Intake of certain types of medicaments (sulfasalazine, anabolic steroids and medicines used in chemotherapy).
• Environmental causes (industrial chemicals, exposure to heavy metals, radiation or X-rays, overheating of the testicles).
• Presence of detrimental habits or leading an unhealthy lifestyle (alcohol and drug abuse, smoking, emotional stress, overweight or obesity).

In some cases, problems occur due to the impossibility of sperm reaching the egg.

These causes are as follows:

• Defected sperm ducts (blockages, inborn defects or physical damage).
• Retrograde ejaculation (if the bladder sphincter doesn’t close during ejaculation- semen is ejaculated into the bladder).
• Immunological infertility (production of anti-sperm antibodies by the immune system, which mistakenly identify sperm as harmful invaders and attempt to eliminate them. These antibodies are the most often related to an injury, surgery or infection).
• Psychological/Physical/Behavioural problems (erectile dysfunction, premature ejaculation and ejaculatory incompetence).

Sometimes these problems can be transitory but at times they require medical treatment and the evaluation of the specialist is the only way to resolve them.