Congenital malformation: A physical 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. In a malformation, the development of a structure is arrested, delayed, or misdirected early in embryonic life and the effect is permanent.
Congenital malformations can 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), 2-3% of babies are born with a major congenital malformation. These infants include many with heart defects, cleft lip or palate, Down syndrome, spina bifida, and limb defects.
Congenital malformations are now the leading cause of infant mortality (death) in the United States (and many other developed nations). They are present in one of every three babies that die in the US.
How a particular congenital malformation affects a child varies. It depends greatly on the severity of the defect and whether or not other medical problems are present. The parents of children with congenital malformations are encouraged to discuss the specifics of the effects of the defect on their child’s current condition with their child’s doctor.
A congenital malformations is also called a birth defect or a congenital anomaly.
source: medterms.com