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Review
. 2017 Jun;44(2):287-303.
doi: 10.1016/j.clp.2017.01.009. Epub 2017 Mar 22.

Survival of Infants Born at Periviable Gestational Ages

Ravi Mangal Patel  1 , Matthew A Rysavy  2 , Edward F Bell  3 , Jon E Tyson  4
Affiliations
Review

Survival of Infants Born at Periviable Gestational Ages

Ravi Mangal Patel et al. Clin Perinatol. 2017 Jun.

Abstract

Periviable births are those occurring from 20 0/7 through 25 6/7 weeks of gestation. Among and within developed nations, significant variation exists in the approach to obstetric and neonatal care for periviable birth. Understanding gestational age-specific survival, including factors that may influence survival estimates and how these estimates have changed over time, may guide approaches to the care of periviable births and inform conversations with families and caregivers. This review provides a historical perspective on survival following periviable birth, summarizes recent and new data on gestational age-specific survival rates, and addresses factors that have a significant impact on survival.

Keywords: Mortality; Perinatal epidemiology; Preterm infant; Resuscitation; Stillbirth.

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Conflict of interest statement

Conflicts of interest: The authors have no conflicts of interest to report.

Figures

Figure 1
Figure 1. Survival from 1993 through 2015 following Live Birth in the NICHD Neonatal Research Network
Includes all participating centers. Liveborn infants were included regardless of whether active treatment was initiated. Whisker bars indicate 95% confidence intervals calculated with the Clopper-Pearson method. Data Stoll BJ, Hansen NI, Bell EF, et al. Trends in care practices, morbidity, and mortality of extremely preterm neonates, 1993–2012. JAMA. 2015;314(10):1039–1051 for 1993–2012 and courtesy of the NICHD Neonatal Research Network for 2013–2015.
Figure 2
Figure 2. Gestational Age-Specific Survival following Live Birth by Study Type
Data are shown for population-based cohorts (gray hues), center-based cohorts reporting survival for live births (blue hues) and center-based cohorts reporting survival for infants admitted to the NICU (orange hues). Characteristics of the data sources are reported in Table 1. Whisker bars indicate 95% confidence intervals calculated with the Clopper-Pearson method. *Estimates not reported by the study.
Figure 3
Figure 3. Potential Birth Outcomes for a Fetus Alive at 20 weeks’ of Gestation
*Although uncommon, survival to NICU admission may occur following initial provision of comfort care.
Figure 4
Figure 4. Periviable Birth Outcomes by Gestational Age in Population-based Studies
Data from population-based studies in France,, the United Kingdom (UK), and Sweden evaluating outcomes of live births and stillbirths in Table 1. Pregnancies with termination not included. Active treatment definitions vary by study but include measures of delivery room intervention or admission for neonatal care.
Figure 5
Figure 5. Changes in Probability of Survival to Discharge Among Infants Alive at a Given Day of Life
Figure denotes changes in probability of survival to hospital discharge for infants who survive to 7 days of life (DOL) and beyond from a cohort of 64,896 infants in 362 US NICUs. Whisker bars indicate 95% confidence intervals calculated with the Clopper-Pearson method Data from Hornik CP, Sherwood AL, Cotten CM, Laughon MM, Clark RH, Smith PB. Daily mortality of infants born at less than 30weeks' gestation. Early Hum Dev. 2016;96:27–30.
See this image and copyright information in PMC

References

    1. Raju TN, Mercer BM, Burchfield DJ, Joseph GF., Jr 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;123(5):1083–1096. - PubMed
    1. American College of Obstetricians and Gynecologists, Society for Maternal-Fetal Medicine et al. Periviable birth: Interim update. Am J Obstet Gynecol. 2016;215(2):B2–B12. e11. - PubMed
    1. Stewart AL, Reynolds EO, Lipscomb AP. Outcome for infants of very low birthweight: survey of world literature. Lancet. 1981;1(8228):1038–1040. - PubMed
    1. Rawlings G, Stewart A, Reynolds EO, Strang LB. Changing prognosis for infants of very low birth weight. Lancet. 1971;1(7698):516–519. - PubMed
    1. Bhat R, Raju TN, Vidyasagar D. Immediate and long-term outcome of infants less than 1000 grams. Crit Care Med. 1978;6(3):147–150. - PubMed

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