Gynecology is the study of the health care of women, including diseases and normal physical care of the female reproductive system. Gynecology also involves the study of female sexual functioning, as well as functioning of the reproductive system and of the secretions (substances released) from hormones in the female body. Hormones are types of chemicals in the body that affect other cells. Gynecologists can perform surgery and also focus on non-surgical care. However, gynecologists do not perform breast surgery. Someone who practices gynecology is known as a gynecologist. Gynecology is commonly abbreviated as GYN.