A few hours after Yahoo announced to the world that Marissa Mayer would be its new CEO, Mayer announced to the world that she was six months pregnant. She was going to work until her due date, she told Fortune magazine, and would only take a few weeks off with her newborn.
It was a bold declaration. Now, a new study suggests, it might even be a dangerous one. The study, published in the July edition of the Journal of Labour Economics (via Global News Online), shows that working in the last month of pregnancy can have as damaging an effect on a baby's weight as smoking.
The study analyzed data from three national surveys, two in the U.K. and one in the U.S. The University of Essex researchers found that working until your water breaks, compared to stopping work between six and eight months, resulted in a newborn who weighed an average of half a pound less -- about a 7 percent drop, given that the average newborn in those countries weighs between between 5.5 pounds to 9.9 pounds. That's slightly less or slightly more of a drop than if the mother smokes, according to various studies. The researchers say possible reasons for this could be fatigue and stress, which hurt the nutritional environment in the womb, according to Global News Online, a Canadian website.
It's also a more dramatic result than if a pregnant woman is hospitalized due to an assault during her pregnancy. According to a study of 5 million pregnant women in California over a 10-year period, infants born to assaulted women weigh one-third of a pound less, on average.
Most women do work into their ninth month of pregnancy. Of women who were pregnant with their first child between 2001 and 2003, 80 percent worked one month or less before their child's birth, compared to 35 percent in 1961-65, according to the U.S. Census Bureau.
American women who have worked at a company for at least a year, and for a company that employs at least 50 people at their location, are allowed to take up to 12 weeks off when they have a child, under the Family and Medical Leave Act. That time off doesn't have to paid, though, and almost half of new mothers in this country don't receive any paid leave at all, including 82 percent of new mothers without a high school degree.
For these women, it comes down to a trade off: working all nine months, and risking a slightly lower birth weight for their child; or not working, and risking how they'll pay for everything else that baby is going to need.
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