While the exact cause of tetralogy of Fallot is unknown, several factors may increase the risk of a baby being born with this condition. These include:

  • A viral illness in the mother, such as rubella (German measles), during pregnancy
  • Maternal alcoholism
  • Poor nutrition
  • A mother older than 40
  • A parent with tetralogy of Fallot
  • Babies who are also born with Down syndrome or DiGeorge syndrome
Feb. 23, 2012