Congenital anomalies refer to abnormalities present at birth, including malformations (abnormal organ formation) and anomalies (abnormal structure or function). Risk factors include advanced maternal age, consanguinity, and malnutrition. Causative factors are genetic factors like chromosomal abnormalities, single gene disorders, and multifactorial inheritance; environmental factors like infections, drug use, radiation, and pollution; and unknown idiopathic causes. Diagnostic tools include prenatal testing like amniocentesis and ultrasound, and postnatal tests like blood tests and imaging. Common types of congenital anomalies affect the nervous, cardiovascular, gastrointestinal, respiratory, genitourinary, musculoskeletal, and endocrine systems.