{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T10:15:29Z","timestamp":1781777729751,"version":"3.54.5"},"reference-count":51,"publisher":"American Academy of Pediatrics (AAP)","issue":"3","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[1998,3,1]]},"abstract":"<jats:p>Objective.\u2003The primary objective of this study was to determine the likelihood of long-term survival and avoidance of disabilities in a geographically based population of infants born at 20 weeks gestation or more and weighing 500 g or less at birth.<\/jats:p><jats:p>Study Design.\u2003This was a 12-year historical cohort follow-up study of all infants born in this gestational age and birth weight category in the Province of Alberta, Canada, between 1983 and 1994. Data were collected from certificates of live births or stillbirths, death certificates, hospital records, and longitudinal multidisciplinary follow-up examinations.<\/jats:p><jats:p>Results.\u2003One thousand one hundred ninety-three infants were of 20 weeks gestation or more, weighed 500 g or less, and were born between 1983 and 1994. Eight hundred eleven (68.0%) were stillborn and 382 (32.0%) were born alive. Among the latter, neonatal intensive care was provided in 113 (29.6%) and withheld in 269 (70.4%). The infants receiving intensive care were of heavier birth weight, later gestational age, higher antenatal risk scores, were more likely to be born in a level III center, to have received antenatal steroids, and to have been delivered by cesarean section. Of the infants receiving intensive care, 95 (84.1%) died and 18 (15.9%) were discharged alive, but 5 of these died after discharge because of respiratory complications. The infants discharged alive had later gestational age, were more likely to be small for gestational age, singletons, treated with antenatal steroids, and to have been delivered by cesarean section. Maternal indications were described in the majority of cesarean sections done for live-born infants. The 13 infants who were long-term survivors were followed at ages 12 and 36 months adjusted age. Four had no serious disabilities, 4 had one disability (cerebral palsy or mental retardation), and 5 had multiple disabilities (cerebral palsy plus mental retardation with blindness in 2 cases and deafness in 1 case).<\/jats:p><jats:p>Conclusion.\u2003The majority of infants born at gestational age 20 weeks or more weighing &amp;lt;500 g were stillborn. Among live births, neonatal intensive care was withheld in 70% and initiated in 30%. Of the latter, 11% survived to 36 months of age, and of these, 4 infants (31%), most of whom are small for gestational age, female infants, avoided major disabilities but 9 (69%) had one or more major disabilities. Survivors are prone to rehospitalizations early in life, slow growth, feeding problems, and minor visual difficulties; rates of learning-related and behavioral problems at school age are not yet known.<\/jats:p><jats:p>Implications.\u2003Parents and caregivers faced with the impending delivery of an infant in this gestational age\/birth weight category should understand that survival without multiple major disabilities is possible but rare. They should be made aware of local population-based results and not just isolated reports.<\/jats:p>","DOI":"10.1542\/peds.101.3.438","type":"journal-article","created":{"date-parts":[[2004,8,13]],"date-time":"2004-08-13T23:44:32Z","timestamp":1092440672000},"page":"438-445","source":"Crossref","is-referenced-by-count":65,"title":["Before Viability: A Geographically Based Outcome Study of Infants Weighing 500 Grams or Less at Birth"],"prefix":"10.1542","volume":"101","author":[{"given":"Reg S.","family":"Sauve","sequence":"first","affiliation":[{"name":"From the Departments of Pediatrics and Community Health Sciences, University of Calgary, Calgary, Alberta, Canada; the"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charlene","family":"Robertson","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, University of Alberta, Glenrose Rehabilitation Hospital, Edmonton, Alberta, Canada; the"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philip","family":"Etches","sequence":"additional","affiliation":[{"name":"Division of Neonatal Medicine, University of Alberta, Royal Alexandra Hospital, Edmonton, Alberta, Canada; the"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul J.","family":"Byrne","sequence":"additional","affiliation":[{"name":"Division of Neonatal Medicine, University of Alberta, University Hospital, Edmonton, Alberta, Canada; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ve\u0301ronique","family":"Dayer-Zamora","sequence":"additional","affiliation":[{"name":"Neonatal-Perinatal Medicine, University of Calgary, Foothills Hospital, Division of Neonatology, Calgary, Alberta, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"417","published-online":{"date-parts":[[1998,3,1]]},"reference":[{"key":"2021121000222763800_B1","doi-asserted-by":"crossref","first-page":"931","DOI":"10.1542\/peds.98.5.931","article-title":"Outcomes of extremely low birth weight infants.","volume":"98","author":"Hack","year":"1996","journal-title":"Pediatrics"},{"key":"2021121000222763800_B2","doi-asserted-by":"crossref","first-page":"1642","DOI":"10.1056\/NEJM198912143212405","article-title":"Outcomes of extremely low birth-weight infants between 1982 and 1988.","volume":"321","author":"Hack","year":"1989","journal-title":"N Engl J Med"},{"key":"2021121000222763800_B3","doi-asserted-by":"crossref","first-page":"1597","DOI":"10.1056\/NEJM199311253292201","article-title":"The limit of viability\u2014neonatal outcome of infants born at 22 to 25 weeks' gestation.","volume":"329","author":"Allen","year":"1993","journal-title":"N Engl J Med"},{"key":"2021121000222763800_B4","doi-asserted-by":"crossref","first-page":"214","DOI":"10.1136\/fn.74.3.F214","article-title":"Perinatal management at the lower margin of viability.","volume":"74","author":"Rennnie","year":"1996","journal-title":"Arch Dis Child"},{"key":"2021121000222763800_B5","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1055\/s-2007-994650","article-title":"The extremely low birthweight infant: the twenty-first century dilemma.","volume":"10","author":"Jakobi","year":"1993","journal-title":"Am J Perinatol"},{"key":"2021121000222763800_B6","first-page":"473","article-title":"From how small is too small to how much is too much: ethical issues at the limits of viability.","volume":"23","author":"Peabody","year":"1994","journal-title":"Clin Perinatol"},{"key":"2021121000222763800_B7","first-page":"4","article-title":"About benefits and costs. 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