In a study that probes the link between working hours and women’s ability to get pregnant, researchers have found that longer the working hours, the harder it is for women to conceive.
Researchers led by Harvard T.H. Chan School of Public Health have found through a study involving 1,739 nurses that women working for more than 40 hours a week take 20 per cent longer to become pregnant than women who work fewer hours.
Not limiting the study to working hours, the researchers also looked at a possible link between heavy lifting at work and women’s chances of conceiving and the findings were startling. They found that women who routinely lift loads of at least 25 pounds several times a day spent about 50 per cent longer trying to conceive compared to women who do not routinely lift that much weight.
“Our results show that heavy work, both in terms of physical strain and long hours, appears to have a detrimental impact on female nurses’ ability to get pregnant,” lead study author Audrey Gaskins, a researcher at Harvard T.H. Chan School of Public Health in Boston, said by email to Reuters.
Researchers reviewed data on women participating in a nationwide survey of nurses between 2010 and 2014 who at some point said they were trying to conceive. Half of the women were at least 33 years old, about 44 percent were overweight or obese and 22 percent were current or former smokers.
The majority of the women worked exclusively days or nights, though 16 percent of them had rotating shifts at different times. About one third of the women were on their feet for at least eight hours a day, and 40 percent reported lifting heavy loads up to five times a daily.
Frequency of night shifts or the duration of rotating or non-rotating evening work wasn’t linked to the time it took women to conceive, the study found.
Based on the data, researchers found that out of the 1,739 nurses who participated in the study, 16 per cent were not able to conceive within 12 months, and 5 per cent were still unable to become pregnant after two years.
“Our results show that heavy work, both in terms of physical strain and long hours, appears to have a detrimental impact on female nurses’ ability to get pregnant,” lead study author Audrey Gaskins, a postdoctoral research fellow in the Department of Nutrition at Harvard Chan School, told Reuters.
The study is published in Occupational and Environmental Medicine.
