Congenital Malformations: Definition and Causes

Definition and Epidemiology

• Congenital malformations are structural or functional anomalies that occur during fetal development, present at birth.
• Also known as birth defects or congenital anomalies.
• Affect approximately 3-4% of live births in the United States.
• Leading cause of infant mortality and morbidity.

Causes and Risk Factors

• Genetic factors:
  • Chromosomal abnormalities (e.g., Down syndrome)
  • Single gene mutations (e.g., cystic fibrosis)
• Environmental factors:
  • Maternal infections (e.g., rubella)
  • Teratogens (e.g., thalidomide)
  • Nutritional deficiencies (e.g., folic acid)
• Multifactorial inheritance:
  • Interaction between genetic and environmental factors

Types of Congenital Malformations

• Craniofacial malformations:
  • Cleft lip and palate
  • Craniosynostosis
• Cardiovascular malformations:
  • Ventricular septal defects
  • Atrial septal defects
  • Tetralogy of Fallot
• Gastrointestinal malformations:
  • Gastrochisis
  • Omphalocele
  • Imperforate anus
• Musculoskeletal malformations:
  • Clubfoot
  • Polydactyly
  • Craniosynostosis
• Neural tube defects:
  • Spina bifida
  • Anencephaly
  • Encephalocele

Detection and Diagnosis

• Prenatal testing:
  • Ultrasound
  • Maternal serum alpha-fetoprotein (MSAFP) screening
  • Chorionic villus sampling (CVS)
  • Amniocentesis
• Postnatal evaluation:
  • Physical examination
  • Imaging studies (e.g., X-ray, CT, MRI)
  • Genetic testing

Management and Treatment

• Prenatal management:
  • Counseling and education
  • Fetal therapy (e.g., surgery)
  • Pregnancy termination
• Postnatal management:
  • Surgical correction
  • Medical management (e.g., medications, therapy)
  • Multidisciplinary team approach

Definition and Epidemiology

• Congenital malformations are structural or functional anomalies that occur during fetal development, present at birth.
• Also known as birth defects or congenital anomalies.
• Affect approximately 3-4% of live births in the United States.
• Leading cause of infant mortality and morbidity.

Causes and Risk Factors

• Genetic factors contribute to congenital malformations, including chromosomal abnormalities (e.g., Down syndrome) and single gene mutations (e.g., cystic fibrosis).
• Environmental factors that contribute to congenital malformations include maternal infections (e.g., rubella), teratogens (e.g., thalidomide), and nutritional deficiencies (e.g., folic acid).
• Multifactorial inheritance involves the interaction between genetic and environmental factors.

Types of Congenital Malformations

Craniofacial Malformations

• Cleft lip and palate
• Craniosynostosis

Cardiovascular Malformations

• Ventricular septal defects
• Atrial septal defects
• Tetralogy of Fallot

Gastrointestinal Malformations

• Gastrochisis
• Omphalocele
• Imperforate anus

Musculoskeletal Malformations

• Clubfoot
• Polydactyly
• Craniosynostosis

Neural Tube Defects

• Spina bifida
• Anencephaly
• Encephalocele

Detection and Diagnosis

Prenatal Testing

• Ultrasound
• Maternal serum alpha-fetoprotein (MSAFP) screening
• Chorionic villus sampling (CVS)
• Amniocentesis

Postnatal Evaluation

• Physical examination
• Imaging studies (e.g., X-ray, CT, MRI)
• Genetic testing

Management and Treatment

Prenatal Management

• Counseling and education
• Fetal therapy (e.g., surgery)
• Pregnancy termination

Postnatal Management

• Surgical correction
• Medical management (e.g., medications, therapy)
• Multidisciplinary team approach