Your immune system is responsible for fighting harmful microorganisms through the production of antibodies that recognize and attack foreign cells, such as bacteria and viruses. Autoimmunity is an inappropriate immune response where your body produces antibodies against your own tissues. There are a number of autoimmune conditions that cause this response, affecting many body systems and organs. Some conditions may affect only a single organ or tissue, whereas others can affect many organs and associated tissues. Both types of autoimmune disorders are implicated in some causes of impaired fertility in women.