Viability of extremely premature neonates: clinical approaches and outcomes

Viability refers to an infant's ability to survive outside the womb, which is influenced by both developmental maturity and the quality of medical care received. The concept of periviability, which has evolved alongside medical advancements, describes the stage between viability and nonviability, typically spanning from 20^0/7 to 25 ^6/7 weeks of gestation. While the chances of survival are extremely low at the earlier end of this range, the possibility of surviving without significant long-term complications improves towards the later end. The effectiveness of various antenatal and postnatal care practices, particularly those considered to be part of an active approach, plays a crucial role in influencing survival rates and mitigating morbidities. However, the decision to provide such active care is heavily influenced by national guidelines as well as international standards. The variability in guideline recommendations from one country to another, coupled with differences based on gestational age or accompanying risk factors, prevents the establishment of a standardized global approach. This variability results in differing practices depending on the country or institution where the birth occurs. Consequently, healthcare providers must navigate these discrepancies, which often leads to complex ethical dilemmas regarding the balance between potential survival and the associated risks. This review article explores the evolution of the definition of viability, the vulnerabilities faced by periviable infants, and the advancements in medical care that have improved survival rates. Additionally, it examines the viability and periviability definitions, the care and outcomes of periviable infants and recommendations in guidelines.