Neonatology is a subspecialty of pediatrics that consists of the medical care of newborn infants, especially the ill or premature newborn. It is a hospital-based specialty and is usually practiced in neonatal intensive care units (NICUs). The principal patients of neonatologists are newborn infants who are ill or require special medical care due to prematurity, low birth weight, intrauterine growth restriction, congenital malformations (birth defects), sepsis, pulmonary hypoplasia or birth asphyxia.
Rather than focusing on a particular organ system, neonatologists focus on the care of newborns who require Intensive Care Unit (ICU) hospitalization. They may also act as general pediatricians, providing well newborn evaluation and care in the hospital where they are based. Some neonatologists, particularly those in academic settings, may follow infants for months or even years after hospital discharge to better assess the long-term effects of health problems early in life. Some neonatologists perform clinical and basic science research to further our understanding of this special population of patients.