Birth defect: Any defect present in a baby at birth, irrespective of whether the defect is caused by a genetic factor or by prenatal events that are not genetic.
Birth defects may involve many different organs including the brain, heart, lungs, liver, bones, and intestinal tract. These defects can occur for many reasons including inherited (genetic) conditions, toxic exposure of the fetus (for example, to alcohol), birth injury and, in many cases, for unknown reasons. All parents are at risk of having a baby with a birth defect, regardless of age, race, income or residence.
In the US (and many other developed nations), 2% to 3% of babies are born with a medically significant birth defect. The infants with birth defects include many with heart defects, cleft lip or palate, Down syndrome, spina bifida, and limb defects.
Birth defects are now the leading cause of infant mortality (death) in the United States (and many other developed nations). Birth defects are present in one of every five babies that die in the US.
How a particular birth defect affects a child varies and depends greatly on the severity of the defect and whether or not other medical problems are present. The parents of children with birth defects are encouraged to discuss the specifics of the effects of the defect on their child's current condition with their child's doctor.
A birth defect is also called a congenital malformation or a congenital anomaly.