WEDNESDAY, April 17, 2002 (HealthDayNews) -- Pressure at work may increase the risk of blood pressure problems for expectant moms.
New research from Ireland suggests that women who work while pregnant face a significantly higher risk of high blood pressure and even preeclampsia, a potentially dangerous condition for both mother and child.
But another expert, aware of the pressures facing modern moms, cautions that it's too early to say that pregnancy and working don't mix, and advises working mothers not to worry that they might be harming themselves or their baby.
The findings appear in the May issue of the Journal of Epidemiology and Community Health.
Preeclampsia is a disorder involving high blood pressure, rapid or obvious swelling that doesn't go away after resting, and protein in the urine; it affects 5 percent of all first-time pregnancies. It typically occurs in middle to late pregnancy and can cause illness or even death in both the mother and infant.
The Irish researchers were monitoring pregnant women's blood pressure to see if they could develop a way to predict who would go on to develop preeclampsia or other blood pressure complications during pregnancy.
The cause of preeclampsia is not known, and the medical literature on work and risk of the condition has had mixed results.
"[Some] studies have suggested that work may predispose [women] to preeclampsia, though some studies haven't," says Dr. John Higgins, the study's lead author and a professor of obstetrics and gynecology at University College Cork.
In this study, Higgins and his colleagues examined 24 hours' worth of ambulatory blood pressure readings from 933 healthy Dublin women pregnant for the first time. The women were divided into groups of those employed, employed but not working on the day of the test, or not employed. The blood pressure readings were taken during weeks 18 to 24 of pregnancy.
Higgins found that when he ruled out the influence of factors including age, body mass index, or smoking or drinking, women who worked had higher overall blood pressure readings that those who were not employed or not at work.
The women didn't specify their occupations, but classified their jobs as sedentary, standing, or active. The researchers found the highest blood pressures in the active group, and the lowest in the sedentary group.
Moreover, the women who worked while pregnant were more than four times as likely to develop preeclampsia.
"We hadn't expected that the association between working and preeclampsia would be as strong," says Higgins.
"It may be that working late into pregnancy is not in the best interests of the mother or the baby," says Higgins. "It may be the physical load of work, but it may also possibly be related to the stress of it."
But he cautions that much more conclusive data would be necessary before they would suggest that it might be unsafe to work during pregnancy.
"Work and pregnancy is now the norm in the Western world," says Higgins. "The pressures of work are that much greater, and the expectations of employers is that much greater, especially for someone who is actively pursuing their career."
Still, he says, "maternal work outside the home is something that needs to be looked at very closely. It's fair to suggest, even based on our preliminary work, that physicians should bear in mind the fact whether a woman who's got high blood pressure is working or not."
Dr. Thomas Easterling, an associate professor of maternal-fetal medicine at the University of Washington in Seattle, says that this shouldn't alarm mothers who choose to work while pregnant.
"There may be something physiological [about] working that increases the risk of preeclampsia, but it doesn't seem to catastrophically increase the risk," he says.
He notes that the overall rate of preeclampsia in the working moms was 4 percent -- close to average -- while nonworking mothers or employed-but-not-working moms had a lower risk.
Easterling also points out that "the preeclampsia did not have a big enough effect in the working group to make them have smaller babies or deliver earlier."
In future studies, the researchers plan to focus on the third trimester of pregnancy as well as the specific factors that may trigger blood pressure problems in pregnant women.
What To Do: Find out more about preeclampsia from the Preeclampsia Foundation, FamilyDoctor.org or the Preeclampsia Research Laboratories.
