Maternal and Child Health Journal

, Volume 16, Issue 5, pp 1031–1044 | Cite as

A Prospective Study of the Association Between Vigorous Physical Activity During Pregnancy and Length of Gestation and Birthweight

  • Anne Marie Z. Jukic
  • Kelly R. Evenson
  • Julie L. Daniels
  • Amy H. Herring
  • Allen J. Wilcox
  • Katherine E. Hartmann
Article

Abstract

Current US pregnancy-related physical activity recommendations do not provide specific guidance for vigorous intensity activity. We examined the associations between vigorous physical activity during pregnancy and length of gestation and birthweight. Methods: Women were recruited before 10 weeks gestation. At 13–16 weeks gestation, participants reported the type, frequency, and duration of their typical weekly vigorous physical activities. Activity domains included recreational, occupational, household, and child/adult care. Infant birth date was obtained from medical or vital records; if unavailable, self-report was used. Birthweight (from vital records) was studied among term births. We analyzed gestational age among 1,647 births using discrete-time survival analysis. We used logistic and linear regression to analyze preterm birth (birth at <37 weeks) and birthweight, respectively. Vigorous recreational activity was associated with longer gestation (any vs. none, hazard ratio (HR) [95% CI]: 0.85 [0.70, 1.05]) and we did not detect any dose–response association. Higher frequency of vigorous recreational activity sessions (adjusted for total volume of activity) was associated with a decreased odds of preterm birth (≥4 sessions/week vs. 0 or 1, OR [95% CI]: 0.08 (0.006, 1.0). Birthweight was not associated with physical activity measures. In summary, vigorous physical activity does not appear to be detrimental to the timing of birth or birthweight. Our data support a reduced risk of preterm birth with vigorous recreational activity, particularly with increased frequency of recreational activity sessions. Future studies should investigate the components of physical activity (i.e., intensity, duration, and frequency) in relation to birth outcomes.

Keywords

Gestational age Preterm birth Exercise Frequency Duration 

Notes

Acknowledgments

This research was supported, in part, by the Intramural Research Program of the National Institute of Health (NIH), National Institute of Environmental Health Sciences (NIEHS). The related components of the parent study, Right From the Start, were funded by NIH, National Institute of Child Health and Development RO1HD043883 and RO1HD049675. This work was also supported in part by NIH/NIEHS T32ES007018 and NIH/NIEHS P30ES10126. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. We would like to thank Dr. Olga Basso and Dr. Shannon Laughlin for their insightful comments.

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Copyright information

© Springer Science+Business Media, LLC (outside the USA)  2011

Authors and Affiliations

  • Anne Marie Z. Jukic
    • 1
    • 2
  • Kelly R. Evenson
    • 1
  • Julie L. Daniels
    • 1
    • 3
  • Amy H. Herring
    • 4
    • 5
  • Allen J. Wilcox
    • 2
  • Katherine E. Hartmann
    • 6
  1. 1.Department of Epidemiology, Gillings School of Global Public HealthUniversity of North Carolina at Chapel HillChapel HillUSA
  2. 2.Epidemiology BranchNational Institute of Environmental Health SciencesDurhamUSA
  3. 3.Department of Maternal and Child Health, Gillings School of Global Public HealthUniversity of North Carolina at Chapel HillChapel HillUSA
  4. 4.Department of Biostatistics, Gillings School of Global Public HealthUniversity of North Carolina at Chapel HillChapel HillUSA
  5. 5.Carolina Population CenterUniversity of North Carolina at Chapel HillChapel HillUSA
  6. 6.Institute for Medicine and Public HealthVanderbilt UniversityNashvilleUSA

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