Objective
We evaluated first-trimester exposures and the risk of preterm birth in the most recent
pregnancy of participants of the Nurses' Health Study II.
Study Design
Log binomial regression was used to estimate the relative risk (RR) for preterm birth
in relation to occupational risk factors, such as work schedule, physical factors,
and exposures to chemicals and x-rays, adjusted for age and parity.
Results
Part-time work (≤ 20 hours a week) was associated with a lower risk of preterm birth
[RR, 0.7; 95% confidence interval [CI], 0.6-0.9]. Working nights was associated only
with early preterm birth (< 32 weeks of gestation) (RR, 3.0; 95% CI, 1.4-6.2). Although
based on only 11 exposed preterm cases, self-reported exposure to sterilizing agents
was associated with an increased risk (RR, 1.9; 95% CI, 1.1-3.4).
Conclusion
These data suggest that night work may be related to early but not late preterm birth,
whereas physically demanding work did not strongly predict risk.
Key words
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Article Info
Publication History
Published online: November 03, 2008
Accepted:
August 1,
2008
Received in revised form:
June 12,
2008
Received:
February 26,
2008
Footnotes
Cite this article as: Lawson CC, Whelan EA, Hibert EN, et al. Occupational factors and risk of preterm birth in nurses. Am J Obstet Gynecol 2009;200;51.e1-51.e8.
This study was supported in part by contract 200-2001-08007 from the Centers for Disease Control and Prevention and the National Institute for Occupational Safety and Health.
The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health.
Identification
Copyright
© 2009 Mosby, Inc. Published by Elsevier Inc. All rights reserved.
