Working too hard can be bad for your unborn baby.
Pregnant women who work physically demanding jobs, long work weeks
or irregular hours may be at increased risk of delivering prematurely
or having an underweight baby, a new study suggests.
Researchers found that among more than 1,100 pregnant women they
followed, those who said their jobs required them to be very physically
active were at increased risk of having a low-birthweight newborn.
Overall, 21 percent of these women delivered an underweight baby,
compared with 14 percent of women with fewer physical demands at work,
according to findings published in medical journal BJOG.
In addition to physical demands, long work hours, shift work and
temporary contract work were all linked to either preterm delivery or
Women who worked 40-plus hours per week or worked a shift schedule
had a heightened risk of delivering an underweight baby. Those doing
temporary contract work, had a four-fold higher risk of preterm
delivery than those with permanent jobs.
The study cannot weed out the reasons for the links, according to
the researchers, led by Dr. Isabelle Niedhammer of the University
College Dublin in Ireland.
In the case of temporary contract work, Niedhammer told Reuters
Health, it may be that these types of jobs carry poorer work
conditions, including higher levels of stress.
For its part, physically demanding work -- including jobs that
require lifting, carrying heavy loads or long periods of standing --
has been linked to adverse effects on pregnancy in previous studies,
Niedhammer pointed out.
In this study, women in low-skill jobs were more likely to perform
shift work, have long worked weeks or work physically demanding jobs.
However, the researchers accounted for factors like women's
education and lifestyle habits such as smoking, and found that work
conditions seemed to affect pregnancy outcomes independently of
According to Niedhammer, the findings suggest that women should talk
to their doctors about their jobs during their first prenatal care
visit -- and, if necessary and possible, make adjustments to their work
And because job conditions are potentially modifiable, she and her
colleagues conclude, more studies should examine how specific
conditions can affect the health of a pregnancy.