-- A
Danish study has found women who worked fixed nighttime hours while pregnant
were more likely to suffer miscarriages.
Jin Liang Zhu of the Danish Epidemiology Research Centre, Aarhus, Denmark,
used data from a Danish nationwide study to identify about 42,000 women who
worked while pregnant. Nearly 34,000 women worked daytime hours only, while
approximately 3,300 worked rotating shifts including night shifts. About 400
women worked fixed nighttime hours.
The risk of miscarriage was 85 percent higher for women who worked a fixed
night shift compared to day workers after adjusting for other factors. The
reasons are unknown; but the researchers said increased estrogen levels related
to night work might play a role.
The results show no effect of working rotating shifts or evening shifts on
the risk of miscarriage.
The findings are published in the November Journal of Occupational and
Environmental Medicine
