A hernia happens when an organ pushes through an opening in the muscle or tissue that holds it in place. For eg, the intestines can break through a weakened area in the abdominal wall or stomach protrudes up through the diaphragm into your chest.
Both male and female are susceptible to getting hernias. Causes can be congenital (ie., you are born with it), developmental or as a result of life activities that wear on muscle tissue as people age. A hernia will not get better over time nor will it ever go away by itself. Hernia usually happens due to stress on the abdominal wall or pressure within the abdomen.