A new study led by Harvard T.H. Chan School of Public Health finds that women who work more than 40 hours a week take 20% longer to become pregnant than women who work fewer hours. They also found that women who routinely lift loads of at least 25 pounds several times a day spent about 50% longer trying to conceive compared to women who do not routinely lift that much weight.
The study, which appeared online August 6, 2015 in Occupational and Environmental Medicine, followed 1,739 female nurses who were trying to get pregnant. The researchers found that 16% of these women had not conceived within 12 months, and 5% 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.
Work schedule and physical factors in relation to fecundity in nurses (Occupational and Environmental Medicine)