Extremely preterm infant: viability and periviable counselling

Overview & Definition

Periviable birth refers to delivery occurring at the borderline of extrauterine viability, typically defined as birth between 20+0 and 25+6 weeks of gestation. ^[8] This is a critical clinical and ethical threshold because each additional week of gestation within this narrow window dramatically alters the probability of survival and the risk of long-term neurodevelopmental impairment. ^[1] The period encompasses the "grey zone" of shared decision-making, generally framed as 22+0 to 24+6 weeks, during which active treatment may or may not be offered depending on parental values, institutional policy, and individualised prognostic factors. ^[8]

Counselling at the threshold of viability is among the most demanding conversations in perinatal medicine. It requires synthesising gestational age estimates, antenatal and intrapartum risk modifiers, institutional outcome data, and the family's values into a shared decision about whether to pursue active resuscitation and intensive care or to provide comfort-focused palliative care. ^[9] The paediatrician's role is to provide honest, balanced, probabilistic information that avoids both false reassurance and undue pessimism, while creating space for genuine parental autonomy. ^[9]

References10ShowHide

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2. [2]Tyson JE Intensive care for extreme prematurity — moving beyond gestational age. N Engl J Med, 2008.PMID 18420500
3. [3]Costeloe KL Short term outcomes after extreme preterm birth in England: comparison of two birth cohorts in 1995 and 2006 (the EPICure studies). BMJ, 2012.PMID 23212881
4. [4]Younge N Survival and Neurodevelopment of Periviable Infants. N Engl J Med, 2017.PMID 28490002
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8. [8]Raju TNK Periviable birth: executive summary of a joint workshop by the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Academy of Pediatrics, and American College of Obstetricians and Gynecologists. Obstet Gynecol, 2014.PMID 24785861
9. [9]Kaempf JW Counseling pregnant women who may deliver extremely premature infants: medical care guidelines, family choices, and neonatal outcomes. Pediatrics, 2009.PMID 19482761
10. [10]Kaempf JW Extremely premature birth and the choice of neonatal intensive care versus palliative comfort care. J Perinatol, 2016.PMID 26583942