Congenital Hypothyroidism in Newborns: Early Detection, Clinical Implications, and Screening Strategies

Congenital hypothyroidism (CH) is one of the most common preventable causes of
intellectual disability worldwide. It results from inadequate production of thyroid
hormones at birth, which are essential for normal brain maturation and physical growth.
The global incidence ranges from approximately 1 in 2,000 to 1 in 4,000 live births,
with regional variability influenced by iodine status and genetic factors. Most affected
newborns appear clinically normal at birth, making early detection through neonatal
screening critical. Without timely treatment, CH may lead to irreversible
neurodevelopmental impairment, growth retardation, and metabolic disturbances.
Measurement of thyroid-stimulating hormone (TSH) and/or thyroxine (T4) levels within
the first days of life forms the cornerstone of screening programs. Early initiation of
levothyroxine therapy significantly improves cognitive outcomes and ensures normal
growth. This article reviews the epidemiology, etiology, clinical features, screening
protocols, and management strategies for congenital hypothyroidism, emphasizing the
importance of universal newborn screening and early therapeutic intervention.