Semin Reprod Med 2016; 34(02): 074-082
DOI: 10.1055/s-0036-1571354
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Fixed or Rotating Night Shift Work Undertaken by Women: Implications for Fertility and Miscarriage

Renae C. Fernandez
1  Discipline of Obstetrics and Gynaecology, University of Adelaide, Adelaide, South Australia, Australia
2  Discipline of Public Health, University of Adelaide, Adelaide, South Australia, Australia
3  Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
,
Jennifer L. Marino
4  Department of Obstetrics and Gynaecology, University of Melbourne, Parkville, Victoria, Australia
5  Royal Women's Hospital, Parkville, Victoria, Australia
,
Tamara J. Varcoe
1  Discipline of Obstetrics and Gynaecology, University of Adelaide, Adelaide, South Australia, Australia
3  Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
,
Scott Davis
6  Department of Epidemiology, School of Public Health, University of Washington, Seattle, Washington
7  Fred Hutchinson Cancer Research Center, Seattle, Washington
,
Lisa J. Moran
1  Discipline of Obstetrics and Gynaecology, University of Adelaide, Adelaide, South Australia, Australia
3  Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
,
Alice R. Rumbold
1  Discipline of Obstetrics and Gynaecology, University of Adelaide, Adelaide, South Australia, Australia
3  Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
,
Hannah M. Brown
1  Discipline of Obstetrics and Gynaecology, University of Adelaide, Adelaide, South Australia, Australia
3  Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
,
Melissa J. Whitrow
2  Discipline of Public Health, University of Adelaide, Adelaide, South Australia, Australia
3  Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
,
Michael J. Davies
1  Discipline of Obstetrics and Gynaecology, University of Adelaide, Adelaide, South Australia, Australia
3  Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
,
Vivienne M. Moore
2  Discipline of Public Health, University of Adelaide, Adelaide, South Australia, Australia
3  Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
8  Fay Gale Centre for Research on Gender, University of Adelaide, Adelaide, South Australia, Australia
› Author Affiliations
Further Information

Publication History

Publication Date:
08 February 2016 (online)

Abstract

This review summarizes the evidence concerning effects of night shift work on women's reproductive health, specifically difficulty in conceiving and miscarriage. We distinguish between fixed night shift and rotating night shift, as the population subgroups exposed, the social and biological mechanisms, and the magnitude of effects are likely to differ; of note, women working fixed night shift are known to have high tolerance for this schedule. We identified two relevant systematic reviews with meta-analyses and five additional studies. Night shift work may give rise to menstrual cycle disturbances, but effect sizes are imprecise. Endometriosis may be elevated in night shift workers, but evidence is only preliminary. Adequate data are lacking to assess associations between night shift work and infertility or time to pregnancy. The weight of evidence begins to point to working at night, whether in fixed or rotating shifts, as a risk factor for miscarriage. There are many methodological problems with this literature, with substantial variation in the definitions of night shift and schedule types making comparisons between studies difficult and pooling across studies questionable. Nevertheless, there appears to be grounds for caution and counselling where women have concerns about night shift work and their reproductive health.