There is no known cause, although some believe that enviromental factors such as pollution play a huge role in this disease/defect.
Congenital heart defects are errors in the development of the heart structure.
hearts with septal defects (holes between pumping chambers)
Most small holes close without treatment. Often, as the child grows, the hole closes or becomes smaller.
Smoking is know to cause premature birth, low birth weight, and premature rupture of membranes, but can possibly cause more serious birth defects.
It can cause the endometrium to not support a pregnancy