What are the types of congenital anomalies?

There are two main categories of congenital anomalies.

Structural Congenital Anomalies

Structural congenital anomalies are related to a problem with the structure of body parts. These can include:

• Cleft lip or cleft palate
• Heart defects, such as missing or misshaped valves
• Atypical limbs, such as a clubfoot
• Neural tube defects, such as spina bifida, and problems related to the growth and development of the brain and spinal cord

Functional or Developmental Congenital Anomalies

Functional or developmental congenital anomalies are related to a problem with how a body part or body system works or functions. These problems can include:

• Nervous system or brain problems. These include intellectual and developmental disabilities, behavioral disorders, speech or language difficulties, seizures, and movement trouble. Some examples of congenital anomalies that affect the nervous system include Down syndrome, Prader-Willi syndrome, and Fragile X syndrome.
• Sensory problems. Examples include hearing loss and visual problems, such as blindness or deafness.
• Metabolic disorders. These involve problems with certain chemical reactions in the body, such as conditions that limit the body’s ability to rid itself of waste materials or harmful chemicals. Two common metabolic disorders are phenylketonuria and hypothyroidism.
• Degenerative disorders. These are conditions that might not be obvious at birth but cause one or more aspects of health to steadily get worse. Examples of degenerative disorders are muscular dystrophy and X-linked adrenoleukodystrophy, which leads to problems of the nervous system and the adrenal glands and was the subject of the movie "Lorenzo’s Oil."

Some congenital anomalies affect many parts or processes in the body, leading to both structural and functional problems.

This information focuses on structural congenital anomalies, their causes, their prevention, and their treatment. Functional/developmental congenital anomalies are addressed more completely in the intellectual and developmental disabilities content.