Working Late Into Pregnancy Just as Harmful as Smoking

Recent data suggests working late into pregancy can cause low birth weight. (Thinkstock)Maternity leave times can vary from job to job, and many expectant moms concerned about their careers can feel pressured to push their last days of work to the limit — often at their desks mere days before their water breaks.

And sometimes it's a matter of necessity, as high living costs demand a dual income to keep the household running.

But a new study published in the Journal of Labor Economics comes with a serious warning for the career-minded. Pregnant women over the age of 24 who toil up to their due date are putting their newborns at risk.

In fact, the research found similar health problems — including lower birth weight and slow development — to babies whose mothers smoked late into their third trimester.

Also see: Canada Ranks Among World's Best Countries for Maternity Leave

"We know low birth weight is a predictor of many things that happen later, including lower chances of completing school successfully, lower wages and higher mortality," study co-author Marco Francesconi tells the Irish Times.

"We need to think seriously about parental leave, because — as this study suggests — the possible benefits of taking leave flexibly before the birth could be quite high."

The data from tens of thousands of women in the U.K. and U.S. showed that babies of mothers who worked — particularly those engaged in physically demanding labour — were on average half a pound lighter than mothers who took it easier between six and eight months.

The children also showed an increase in health problems that plagued them later in life.

The same statistics applied to mothers who smoked throughout their gestation.

Also see: 10 Worst Pieces of Parenting Advice We've Ever Received

Statistics Canada reveals that in 2010-11, 83 per cent of mothers took some form of paid leave after giving birth, while one in five took unpaid leave.

The average paid leave rang in at 40 weeks, while women on unpaid leave took an average of 4.5 weeks to be with their newborns.

Though Canada ranks behind Sweden's 16-month paid mat leave, it definitely beats the 12 unpaid weeks offered to new moms in the U.S.

Still, as Canadian Business reports, pregnant workers may feel pressured to push themselves to the limit based on their employer's personal attitude toward maternity leave laws.

Employment lawyer Daniel Lublin tells the magazine most businesses aren't too fond of the country's reinstatement laws that demand employers hire a worker back after time off with her baby.

"Companies need to be able to react to the market. They don't like being hamstrung by an obligation to reinstate someone, especially someone who [may not have been] great to begin with," he says.

A woman who internalizes that obligation may be predisposed to give it her all as close to her due date as possible.

Though there's no guarantee the study's results will inspire new legislation, Francesconi says he hopes governments would offer more "flexible" options to women who may need to put up their feet before, and not simply after, her baby is born.

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