The University of Southampton
University of Southampton Institutional Repository

Miscarriage and occupational activity: a systematic review and meta-analysis regarding shift work, working hours, lifting, standing and physical workload

Miscarriage and occupational activity: a systematic review and meta-analysis regarding shift work, working hours, lifting, standing and physical workload
Miscarriage and occupational activity: a systematic review and meta-analysis regarding shift work, working hours, lifting, standing and physical workload
OBJECTIVE: Previous studies have indicated that shift work, long working hours, and prevalent workplace exposures such as lifting, standing, and physical workload increase the risk of miscarriage, but the evidence is conflicting. We conducted a systematic review of original research reports.

METHODS: A search in Medline and EMBASE 1966-2012 identified 30 primary papers reporting the relative risk (RR) of miscarriage according to ?1 of 5 occupational activities of interest. Following an assessment of completeness of reporting, confounding, and bias, each risk estimate was characterized as more or less likely to be biased. Studies with equivalent measures of exposure were pooled to obtain a weighted common risk estimate. Sensitivity analyses excluded studies most likely to be biased.

RESULTS: Working fixed nights was associated with a moderately increased risk of miscarriage (pooled RR 1.51 [95% confidence interval (95% CI) 1.27-1.78, N=5), while working in 3-shift schedules, working for 40-52 hours weekly, lifting >100 kg/day, standing >6-8 hours/day and physical workload were associated with small risk increments, with the pooled RR ranging from 1.12 (3-shift schedule, N=7) to 1.36 (working hours, N=10). RR for working hours and standing became smaller when analyses were restricted to higher quality studies.

CONCLUSIONS: These largely reassuring findings do not provide a strong case for mandatory restrictions in relation to shift work, long working hours, occupational lifting, standing, and physical workload. Considering the limited evidence base, however, it may be prudent to advise women against work entailing high levels of these exposures and women with at-risk pregnancies should receive tailored individual counseling.
counselling, embryonal loss, fetal death, guidelines, pregnancy, occupation, workplace
0355-3140
325-334
Bonde, J.P.
1ecb9620-1893-45be-baf1-84a744610876
Jorgensen, K.T.
890b04b7-8e3d-4562-81a3-85afc2f021f6
Bonzini, M.
0cd0ca2c-a67c-4ec4-95ee-7c93060d47a1
Palmer, K.T.
0cfe63f0-1d33-40ff-ae8c-6c33601df850
Bonde, J.P.
1ecb9620-1893-45be-baf1-84a744610876
Jorgensen, K.T.
890b04b7-8e3d-4562-81a3-85afc2f021f6
Bonzini, M.
0cd0ca2c-a67c-4ec4-95ee-7c93060d47a1
Palmer, K.T.
0cfe63f0-1d33-40ff-ae8c-6c33601df850

Bonde, J.P., Jorgensen, K.T., Bonzini, M. and Palmer, K.T. (2013) Miscarriage and occupational activity: a systematic review and meta-analysis regarding shift work, working hours, lifting, standing and physical workload. Scandinavian Journal of Work, Environment & Health, 39 (4), 325-334. (doi:10.5271/sjweh.3337). (PMID:23235838)

Record type: Article

Abstract

OBJECTIVE: Previous studies have indicated that shift work, long working hours, and prevalent workplace exposures such as lifting, standing, and physical workload increase the risk of miscarriage, but the evidence is conflicting. We conducted a systematic review of original research reports.

METHODS: A search in Medline and EMBASE 1966-2012 identified 30 primary papers reporting the relative risk (RR) of miscarriage according to ?1 of 5 occupational activities of interest. Following an assessment of completeness of reporting, confounding, and bias, each risk estimate was characterized as more or less likely to be biased. Studies with equivalent measures of exposure were pooled to obtain a weighted common risk estimate. Sensitivity analyses excluded studies most likely to be biased.

RESULTS: Working fixed nights was associated with a moderately increased risk of miscarriage (pooled RR 1.51 [95% confidence interval (95% CI) 1.27-1.78, N=5), while working in 3-shift schedules, working for 40-52 hours weekly, lifting >100 kg/day, standing >6-8 hours/day and physical workload were associated with small risk increments, with the pooled RR ranging from 1.12 (3-shift schedule, N=7) to 1.36 (working hours, N=10). RR for working hours and standing became smaller when analyses were restricted to higher quality studies.

CONCLUSIONS: These largely reassuring findings do not provide a strong case for mandatory restrictions in relation to shift work, long working hours, occupational lifting, standing, and physical workload. Considering the limited evidence base, however, it may be prudent to advise women against work entailing high levels of these exposures and women with at-risk pregnancies should receive tailored individual counseling.

Text
Miscarriage review manuscript final 27.9.2012 revised 28.11.2012.doc - Author's Original
Download (263kB)

More information

Published date: 1 July 2013
Keywords: counselling, embryonal loss, fetal death, guidelines, pregnancy, occupation, workplace
Organisations: Faculty of Medicine

Identifiers

Local EPrints ID: 355677
URI: http://eprints.soton.ac.uk/id/eprint/355677
ISSN: 0355-3140
PURE UUID: e31f8f7b-ad36-465d-a2f2-0ce416f321d4

Catalogue record

Date deposited: 03 Sep 2013 13:41
Last modified: 16 Dec 2019 20:30

Export record

Altmetrics

Contributors

Author: J.P. Bonde
Author: K.T. Jorgensen
Author: M. Bonzini
Author: K.T. Palmer

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×