The most common type of congenital hemolytic anemia is called hereditary spherocytosis (HS). HS is an inherited disorder caused by a genetic defect that affects the shape of red blood cells. The cells become rounder, thus reducing their ability to carry oxygen throughout the body. It can also cause anemia, or a decrease in red blood cell count. HS is one of the most common inherited disorders of the red blood cells. It usually affects people of all ages, but tends to be more common in children and young adults. Symptoms may include fatigue, jaundice, and shortness of breath. Treatment typically involves taking iron supplements, as well as medications to help reduce the destruction of red blood cells.