Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Commentary
  • Published:

Fetal, neonatal and infant death and their relationship to best gestational age for delivery at term: is 39 weeks best for everyone?

Journal of Perinatology volume 34, pages 503–507 (2014)Cite this article

Subjects

Recent recommendations have stated that ‘non-medically indicated delivery before 39 weeks gestation should be avoided.’ The current work examines much of the published national data used as a foundation for those recommendations, which are based on stated improvements to fetal, neonatal and infant mortality as well as neonatal morbidity. In this work, each of these factors is analyzed, with a specific aim to delineate the role of week of gestation along with other possible confounding variables affecting outcome, and to explain several methodological shortcomings that have characterized the research up to now. The analysis suggests that delaying delivery until 39 weeks would increase fetal deaths and have little or no influence on neonatal and infant deaths. Further, confounding factors that effect both neonatal and maternal morbidity have not been adequately examined. Decisions aimed at optimizing perinatal outcomes require simultaneous consideration of multiple, complex, inter-related dynamic factors and would be highly unlikely to be optimized with a simple recommendation such as ‘avoidance of delivery before 39 weeks.’ It is the aim of this work to encourage current stakeholders to recognize the need to re-examine this issue, with an understanding that an individualized approach to decisions regarding the timing of delivery at term is essential. Proper analysis of current and future data will likely point to a different approach that is clearly away from the same recommendation for all.

A series of publications have examined perinatal outcomes at term. These studies have included both large patient samples as well as regional and national data.1, 2, 3, 4, 5, 6 The results of these analyses seemed to indicate a consistent pattern: delivery at gestational ages before 39 weeks gestation results in an increase in adverse perinatal outcomes. As additional data were accumulated with similar findings, the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the Society for Maternal Fetal Medicine held a workshop in February 2011 (entitled ‘Timing of indicated late-preterm and early-term births’) to discuss and evaluate the published data. The workshop culminated in recommendations regarding both indicated and elective delivery during the late-preterm and early-term period of pregnancy.7 For elective deliveries, the task force interpreted the data as indicating that elective delivery before 39 weeks gestation must be avoided in order to minimize adverse outcomes. Subsequently, the American Congress of Obstetricians and Gynecologists issued a committee opinion reinforcing the conclusions of the NICHD.8, 9 In June of 2013, these data were used as the basis for an editorial, which reinforced the proposition that ‘given the known excess morbidity and mortality risk prior to 39 weeks, it is essential not to undertake nonmedically indicated delivery before reaching this date.’10 As 4 million deliveries occur annually in the United States, with the majority reaching 37 weeks gestation, millions of women and their physicians are confronted with decisions regarding timing of delivery as pregnancy reaches 37 weeks gestation. These decisions obviously have a direct effect on the outcome for the patients and their babies.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1
Figure 2
Figure 3

References

  1. Hibbard JU, Wilkins I, Sun L, Gregory K, Haberman S, Hoffman M et al. Respiratory morbidity in later preterm births by the consortium on safe labor. JAMA 2010; 304 (4): 419–425.

    Article  CAS  PubMed Central  Google Scholar 

  2. Reddy UM, Ko CW, Raju TN, Willinger M . Delivery indications in later-preterm gestations and infant mortality rates in the United States. Pediatrics 2009; 124 (1): 234–240.

    Article  PubMed Central  Google Scholar 

  3. Tomashek KM, Shapiro-Mendoza CK, Davidoff MJ, Petrini JR . Differences in mortality between later-preterm and term singleton infants in the United States, 1995–2002. J Pediatr 2007; 151 (5): 450–456.

    Article  Google Scholar 

  4. Tita AT, Landon MB, Spong CY, Lai Y, Leveno KJ, Varner MW et al. Timing of elective repeat cesarean delivery at term and neonatal outcomes. N Engl J Med 2009; 360 (2): 111–120.

    Article  CAS  PubMed Central  Google Scholar 

  5. Bailit JL, Gregory KD, Reddy UM, Gonzalez-Quintero VH, Hibbard JU, Ramirez MM et al. Maternal and neonatal outcomes by labor onset type and gestational age. Am J Obstet Gynecol 2010; 202: 245.e1–e12.

    Article  Google Scholar 

  6. Reddy U, Bettegowda VR, Dias T, Yamada-Kushnir T, Ko CW, Willinger M . Term pregnancy: a period of heterogeneous risk for infant mortality. Obstet Gynecol 2011; 117 (6): 1279–1287.

    Article  PubMed Central  Google Scholar 

  7. Spong CY, Mercer BM, D’alton M, Kilpatrick S, Blackwell S, Saade G . Timing of indicated later-preterm and early-term birth. Obstet Gynecol 2011; 118 (2 Pt 1): 323–333.

    Article  PubMed Central  Google Scholar 

  8. American College of Obstetricians and Gynecologists. ACOG committee opinion no. 560: Medically indicated late-preterm and early-term deliveries. Obstet Gynecol 2013; 121 (4): 908–910.

    Article  Google Scholar 

  9. American College of Obstetricians and Gynecologists. ACOG committee opinion no. 561: Nonmedically indicated early-term deliveries. Obstet Gynecol 2013; 121 (4): 911–915.

    Article  Google Scholar 

  10. Spong C . Defining term pregnancy. JAMA 2013; 309 (23): 2445–2446.

    Article  CAS  Google Scholar 

  11. Yudkin PL, Wood L, Redmna CW . Risk of unexplained stillbirth at different gestational ages. Lancet 1987; 1 (8543): 1192–1194.

    Article  CAS  Google Scholar 

  12. Ferguson R, Myers SA . The effect of race on the relationship between fetal death and altered fetal growth. Am J Obstet Gynecol 1990; 163 (4 Pt 1): 1222–1230.

    Article  CAS  Google Scholar 

  13. Ferguson R, Myers SA . Population study of the risk of fetal death and its relationship to birthweight, gestational age, and race. Am J Perinatol 1994; 11 (4): 267–272.

    Article  CAS  Google Scholar 

  14. Rand L, Robinson JN, Economy KE, Norwitz ER . Post-term induction of labor revisited. Obstet Gynecol 2000; 96 (5 Pt 1): 779–783.

    CAS  PubMed  Google Scholar 

  15. Smith GC . Life-table analysis of the risk of perinatal death at term and post term in singleton pregnancies. Am J Obstet Gynecol 2001; 184 (3): 489–496.

    Article  CAS  Google Scholar 

  16. MacDorman MF, Kirmeyer SE, Wilson ED . Fetal and perinatal mortality, United States, 2006. Natl Vital Stat Rep 2012; 60 (8): 1–23.

    PubMed  Google Scholar 

  17. Mandujano A, Waters TP, Myers SA . The risk of fetal death: current concepts of best gestational age for delivery. Am J Obstet Gynecol 2013; 208: 207.e1–e8.

    Article  Google Scholar 

  18. Callaghan WM, MacDorman MF, Rasmussen SA, Qin C, Lackritz EM . The contribution of preterm birth to infant mortality rates in the United States. Pediatrics 2006; 118 (4): 1566.

    Article  Google Scholar 

  19. Dumville JC, Torgerson DJ, Hewitt CE . Reporting attrition in randomized controlled trials. Br Med J 2006; 332 (7547): 969–971.

    Article  Google Scholar 

  20. Feinstein AR . Clinical Epidemiology: The Architecture of Clinical Research. WB Saunders: Philadelphia, PA, USA, 1985.

    Google Scholar 

  21. Gibbs RS, Romero R, Hillier SL, Eschenbach DA, Sweet RL . A review of premature birth and subclinical infection. Am J Obstet Gynecol 1992; 166 (5): 1515–1528.

    Article  CAS  Google Scholar 

  22. Page JM, Snowden JM, Cheng YW, Doss AE, Rosenstein MG, Caughey AB . The risk of stillbirth and infant death by each additional week of expectant management stratified by maternal age. Am J Obstet Gynecol 2013; 209: 375.e1–e7.

    Article  Google Scholar 

  23. Caughey AB . Measuring perinatal complications: methodologic issues related to gestational age. BMC Pregnancy Childbirth 2007; 7: 18.

    Article  PubMed Central  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Obstetrics and Gynecology, MetroHealth Medical Center/Case Western Reserve University, Cleveland, OH, USA

    S A Myers

  2. Department of Obstetrics and Gynecology, Loyola University Medical Center, Maywood, IL, USA

    T P Waters

  3. Center for Health Care Research and Policy, Case Western Reserve University at MetroHealth Medical Center, Cleveland, OH, USA

    N V Dawson

Authors
  1. S A Myers
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. T P Waters
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. N V Dawson
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to S A Myers.

Ethics declarations

Competing interests

The authors declare no conflict of interest.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Myers, S., Waters, T. & Dawson, N. Fetal, neonatal and infant death and their relationship to best gestational age for delivery at term: is 39 weeks best for everyone?. J Perinatol 34, 503–507 (2014). https://doi.org/10.1038/jp.2014.9

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/jp.2014.9

Search

Advanced search

Quick links