Incidence and mortality of the premature infant
- George T Mandy, MD
George T Mandy, MD
- Associate Professor of Pediatrics
- Baylor College of Medicine
Prematurity is defined as a birth that occurs before 37 completed weeks (less than 259 days) of gestation. It is associated with approximately one-third of all infant deaths in the United States. Infants born at or before 25 weeks of gestation have the highest mortality rate (about 50 percent) and if they survive, are at the greatest risk for severe impairment .
The incidence and mortality rate of preterm birth will be reviewed here. The risk and pathogenesis of preterm birth and complications of prematurity are discussed separately. (See "Risk factors for preterm labor and delivery" and "Pathogenesis of spontaneous preterm birth" and "Short-term complications of the premature infant".)
Different degrees of prematurity are defined by gestational age (GA), which is calculated from the first day of the mother's last period, or birthweight (BW).
One classification based upon BW includes the following categories (table 1):
●Low birth weight (LBW) – BW less than 2500 g
- Mathews TJ, MacDorman MF. Infant mortality statistics from the 2005 period linked birth/infant death data set. Natl Vital Stat Rep 2008; 57:1.
- WHO, March of Dimes, Partnership for Maternal, Newborn & Child Health, Save the Children. Born too soon: the global action report on preterm birth. www.who.int/maternal_child_adolescent/documents/born_too_soon/en/ (Accessed on May 04, 2012).
- Blencowe H, Cousens S, Oestergaard MZ, et al. National, regional, and worldwide estimates of preterm birth rates in the year 2010 with time trends since 1990 for selected countries: a systematic analysis and implications. Lancet 2012; 379:2162.
- Hamilton BE, Hoyert DL, Martin JA, et al. Annual summary of vital statistics: 2010-2011. Pediatrics 2013; 131:548.
- Hamilton BE, Martin JA, Ventura SJ. Births: Preliminary data for 2011. Natl Vital Stat Rep 2012. http://www.cdc.gov/nchs/data/nvsr/nvsr61/nvsr61_05.pdf (Accessed on March 12, 2013).
- Markestad T, Kaaresen PI, Rønnestad A, et al. Early death, morbidity, and need of treatment among extremely premature infants. Pediatrics 2005; 115:1289.
- Teitler JO, Reichman NE, Nepomnyaschy L, Martinson M. A cross-national comparison of racial and ethnic disparities in low birth weight in the United States and England. Pediatrics 2007; 120:e1182.
- Behrman RE, Butler AS. Preterm Birth, Causes, Consequences, and Prevention, The National Academies Press, Washington, DC 2007.
- Mathews TJ, MacDorman MF. Infant mortality statistics from the 2009 period linked birth/infant death data set. National Vital Statistics Reports 2013;61:1. http://www.cdc.gov/nchs/data/nvsr/nvsr61/nvsr61_08.pdf (Accessed on July 10, 2013).
- Katz J, Lee AC, Kozuki N, et al. Mortality risk in preterm and small-for-gestational-age infants in low-income and middle-income countries: a pooled country analysis. Lancet 2013; 382:417.
- Zeitlin J, El Ayoubi M, Jarreau PH, et al. Impact of fetal growth restriction on mortality and morbidity in a very preterm birth cohort. J Pediatr 2010; 157:733.
- Tyson JE, Parikh NA, Langer J, et al. Intensive care for extreme prematurity--moving beyond gestational age. N Engl J Med 2008; 358:1672.
- Field DJ, Dorling JS, Manktelow BN, Draper ES. Survival of extremely premature babies in a geographically defined population: prospective cohort study of 1994-9 compared with 2000-5. BMJ 2008; 336:1221.
- Itabashi K, Horiuchi T, Kusuda S, et al. Mortality rates for extremely low birth weight infants born in Japan in 2005. Pediatrics 2009; 123:445.
- Bassler D, Stoll BJ, Schmidt B, et al. Using a count of neonatal morbidities to predict poor outcome in extremely low birth weight infants: added role of neonatal infection. Pediatrics 2009; 123:313.
- Wyckoff MH, Salhab WA, Heyne RJ, et al. Outcome of extremely low birth weight infants who received delivery room cardiopulmonary resuscitation. J Pediatr 2012; 160:239.
- Kent AL, Wright IM, Abdel-Latif ME, New South Wales and Australian Capital Territory Neonatal Intensive Care Units Audit Group. Mortality and adverse neurologic outcomes are greater in preterm male infants. Pediatrics 2012; 129:124.
- Mathews TJ, MacDorman MF. Infant mortality statistics from the 2004 period linked birth/infant death data set. Natl Vital Stat Rep 2007; 55:1.
- Premature birth in the United States black population. Available at: www.marchofdimes.com/files/AA_PTB_Report_FINAL910.pdf/ (Accessed on June 06, 2008).
- Lemons JA, Bauer CR, Oh W, et al. Very low birth weight outcomes of the National Institute of Child health and human development neonatal research network, January 1995 through December 1996. NICHD Neonatal Research Network. Pediatrics 2001; 107:E1.
- Fanaroff AA, Stoll BJ, Wright LL, et al. Trends in neonatal morbidity and mortality for very low birthweight infants. Am J Obstet Gynecol 2007; 196:147.e1.
- Bode MM, D'Eugenio DB, Forsyth N, et al. Outcome of extreme prematurity: a prospective comparison of 2 regional cohorts born 20 years apart. Pediatrics 2009; 124:866.
- Zeitlin J, Ancel PY, Delmas D, et al. Changes in care and outcome of very preterm babies in the Parisian region between 1998 and 2003. Arch Dis Child Fetal Neonatal Ed 2010; 95:F188.
- Horbar JD, Carpenter JH, Badger GJ, et al. Mortality and neonatal morbidity among infants 501 to 1500 grams from 2000 to 2009. Pediatrics 2012; 129:1019.
- Costeloe KL, Hennessy EM, Haider S, et al. Short term outcomes after extreme preterm birth in England: comparison of two birth cohorts in 1995 and 2006 (the EPICure studies). BMJ 2012; 345:e7976.
- Marlow N, Bennett C, Draper ES, et al. Perinatal outcomes for extremely preterm babies in relation to place of birth in England: the EPICure 2 study. Arch Dis Child Fetal Neonatal Ed 2014; 99:F181.
- Phibbs CS, Baker LC, Caughey AB, et al. Level and volume of neonatal intensive care and mortality in very-low-birth-weight infants. N Engl J Med 2007; 356:2165.
- Watson SI, Arulampalam W, Petrou S, et al. The effects of designation and volume of neonatal care on mortality and morbidity outcomes of very preterm infants in England: retrospective population-based cohort study. BMJ Open 2014; 4:e004856.
- Centers for Disease Control and Prevention (CDC). Neonatal intensive-care unit admission of infants with very low birth weight --- 19 States, 2006. MMWR Morb Mortal Wkly Rep 2010; 59:1444.
- Acolet D, Elbourne D, McIntosh N, et al. Project 27/28: inquiry into quality of neonatal care and its effect on the survival of infants who were born at 27 and 28 weeks in England, Wales, and Northern Ireland. Pediatrics 2005; 116:1457.
- American Academy of Pediatrics Committee on Fetus And Newborn. Levels of neonatal care. Pediatrics 2012; 130:587.
- Alleman BW, Bell EF, Li L, et al. Individual and center-level factors affecting mortality among extremely low birth weight infants. Pediatrics 2013; 132:e175.
- Corchia C, Ferrante P, Da Frè M, et al. Cause-specific mortality of very preterm infants and antenatal events. J Pediatr 2013; 162:1125.
- Feng Y, Abdel-Latif ME, Bajuk B, et al. Causes of death in infants admitted to Australian neonatal intensive care units between 1995 and 2006. Acta Paediatr 2013; 102:e17.
- Lawn JE, Wilczynska-Ketende K, Cousens SN. Estimating the causes of 4 million neonatal deaths in the year 2000. Int J Epidemiol 2006; 35:706.
- Walden RV, Taylor SC, Hansen NI, et al. Major congenital anomalies place extremely low birth weight infants at higher risk for poor growth and developmental outcomes. Pediatrics 2007; 120:e1512.
- Pappas A, Shankaran S, Hansen NI, et al. Outcome of extremely preterm infants (<1,000 g) with congenital heart defects from the National Institute of Child Health and Human Development Neonatal Research Network. Pediatr Cardiol 2012; 33:1415.
- Boghossian NS, Horbar JD, Carpenter JH, et al. Major chromosomal anomalies among very low birth weight infants in the Vermont Oxford Network. J Pediatr 2012; 160:774.
- Mohamed MA, Nada A, Aly H. Day-by-day postnatal survival in very low birth weight infants. Pediatrics 2010; 126:e360.
- Stoll BJ, Hansen NI, Bell EF, et al. Neonatal outcomes of extremely preterm infants from the NICHD Neonatal Research Network. Pediatrics 2010; 126:443.
- De Jesus LC, Pappas A, Shankaran S, et al. Risk factors for post-neonatal intensive care unit discharge mortality among extremely low birth weight infants. J Pediatr 2012; 161:70.
- Swamy GK, Ostbye T, Skjaerven R. Association of preterm birth with long-term survival, reproduction, and next-generation preterm birth. JAMA 2008; 299:1429.
- Multiple gestation and ART
- PATHOGENESIS FOR PRETERM BIRTH
- Risk factors for preterm birth
- Gestational age and birth weight
- - Extremely preterm infants
- - Late preterm infants
- Level of neonatal care
- - Trends over time
- - Standard of neonatal care
- AAP policy
- - Center variation
- Congenital anomalies
- Time of death during birth hospitalization
- Post-discharge mortality
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS