limit of viabilityJoe Segen2016-11-11T20:33:09+00:00
limit of viability
A term of art for the degree of fetal maturity which ensures a reasonable chance of extrauterine survival.
Factors affecting survival in extremely (<26 weeks) premature infants Gestational age, birth weight, gender, plurality, use of antenatal corticosteroid therapy.
Determining the limit of viability is desirable so that costly, painful and ineffective interventions can be avoided in infants with little chance of survival.
Limits of Viability
Weeks of Gestation 22 23 24 25
Average birthweight (g) 490 592 695 761
Per cent stillbirth 25% 10% 0% 0%
Per cent 6-month survival 0% 15% 56% 80%
Days of hospital stay NA 120±23 107±37 76±23
Survival w/o brain defects 0% 12% 21% 69%
Synonym Threshold of viability