Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2012 Mar 1:344:e896.
doi: 10.1136/bmj.e896.

Effects of gestational age at birth on health outcomes at 3 and 5 years of age: population based cohort study

Elaine M Boyle  1 , Gry Poulsen, David J Field, Jennifer J Kurinczuk, Dieter Wolke, Zarko Alfirevic, Maria A Quigley
Affiliations

Effects of gestational age at birth on health outcomes at 3 and 5 years of age: population based cohort study

Elaine M Boyle et al. BMJ. .

Abstract

Objective: To investigate the burden of later disease associated with moderate/late preterm (32-36 weeks) and early term (37-38 weeks) birth.

Design: Secondary analysis of data from the Millennium Cohort Study (MCS).

Setting: Longitudinal study of infants born in the United Kingdom between 2000 and 2002.

Participants: 18,818 infants participated in the MCS. Effects of gestational age at birth on health outcomes at 3 (n = 14,273) and 5 years (n = 14,056) of age were analysed.

Main outcome measures: Growth, hospital admissions, longstanding illness/disability, wheezing/asthma, use of prescribed drugs, and parental rating of their children's health.

Results: Measures of general health, hospital admissions, and longstanding illness showed a gradient of increasing risk of poorer outcome with decreasing gestation, suggesting a "dose-response" effect of prematurity. The greatest contribution to disease burden at 3 and 5 years was in children born late/moderate preterm or early term. Population attributable fractions for having at least three hospital admissions between 9 months and 5 years were 5.7% (95% confidence interval 2.0% to 10.0%) for birth at 32-36 weeks and 7.2% (1.4% to 13.6%) for birth at 37-38 weeks, compared with 3.8% (1.3% to 6.5%) for children born very preterm (<32 weeks). Similarly, 2.7% (1.1% to 4.3%), 5.4% (2.4% to 8.6%), and 5.4% (0.7% to 10.5%) of limiting longstanding illness at 5 years were attributed to very preterm birth, moderate/late preterm birth, and early term birth.

Conclusions: These results suggest that health outcomes of moderate/late preterm and early term babies are worse than those of full term babies. Additional research should quantify how much of the effect is due to maternal/fetal complications rather than prematurity itself. Irrespective of the reason for preterm birth, large numbers of these babies present a greater burden on public health services than very preterm babies.

PubMed Disclaimer

Conflict of interest statement

Competing interests: All authors have completed the Unified Competing Interest form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.

Figures

None
Fig 1 Flow chart of eligibility and participation
None
Fig 2 Classification of weight status according to body mass index at 3 and 5 years for gestational age groups
See this image and copyright information in PMC

References

    1. Wood NS, Marlow N, Costeloe K, Gibson AT, Wilkinson AR. Neurologic and developmental disability after extremely preterm birth. N Engl J Med 2000;343:378-84. - PubMed
    1. Moser K, Macfarlane A, Chow YH, Hilder L, Dattani N. Introducing new data on gestation-specific infant mortality among babies born in 2005 in England and Wales. Health Stat Q 2007;13:27. - PubMed
    1. Kramer MS, Demissie K, Yang H, Platt RW, Sauve R, Liston R. The contribution of mild and moderate preterm birth to infant mortality. JAMA 2000;284:843-9. - PubMed
    1. Tomashek KM, Shapiro-Mendoza CK, Davidoff MJ, Petrini JR. Differences in mortality between late-preterm and term singleton infants in the United States, 1995-2002. J Pediatr 2007;151:450-6,456.e1. - PubMed
    1. Escobar GJ, Clark RH, Greene JD. Short-term outcomes of infants born at 35 and 36 weeks’ gestation: we need to ask more questions. Semin Perinatol 2006;30:28-33. - PubMed

Publication types

MeSH terms