Researcher’s analyzed data of 1,739 women with an average age of 33 who participated in the 2010–2014 Nurses’ Health Study. Each woman was attempting to get pregnant. At the beginning of the study, participants complete a questionnaire that detailed their work schedules and physical labor.
Every six months, researchers assessed participants to determine how long it was taking them to get pregnant.
Approximately 44% of participants were overweight or obese and 22% were present or former smokers. The majority of women worked days or nights only, while 16% worked rotating shifts. Over 30% of women reported working more than eight hours daily and 40% reported that they lifted heavy loads at least five times a day.
After a 12-month period, 16% of participants reported that they had not become pregnant and five percent had not conceived after two years. Compared to women who worked 21–40 hours a week, participants who worked more than 40 hours a week took about 20% longer to get pregnant.
Researchers also found that women who lifted or moved at least 25 pounds more than 15 times a day took approximately 50% longer to get pregnant compared to women who did not lift or move heavy loads.
Sources for Today’s Article:
Gaskins, A.J., et al., “Work schedule and physical factors in relation to fecundity in nurses,” Occupational & Environmental Medicine, http://www.ncbi.nlm.nih.gov/pubmed/26251064, doi: 10.1136/oemed-2015-103026, published online August 6, 2015.
Whiteman, H., “Working more than 40 hours weekly may increase time to conception by 20%,” Medical News Today web site, August 17, 2015; http://www.medicalnewstoday.com/articles/298219.php.