Smokers Have Lower Risk For Preeclampsia
Everyone knows that pregnant women shouldn't smoke for all kinds of reasons. But a new study says that women who smoke during gestation have a decreased risk for the pregnancy complication known as preeclampsia. This finding may help to explain the mechanics of how this complication comes to pass.
The researchers caution that their results should not deemphasize the importance of quitting smoking in women who are pregnant. In fact, women should quit before they even attempt to conceive. Smoking in pregnancy has been linked to a higher rate of miscarriage, low birth weights, and a variety of other complications of pregnancy.
However, if researchers can pinpoint just how smoking relates to lowering the risk for preeclampsia, they might find new therapies or preventative measures for this pregnancy complication. This is according to Dr. Anna-Karin Wikstrom, who is the lead author for this study.
Preeclampsia comes with a sudden, marked increase in blood pressure that occurs some time after the 20th week of gestation. One symptom of the condition is the buildup of protein in the pregnant woman's urine. If preeclampsia is not responded to with prompt treatment, it may progress to the sometimes fatal condition known as eclampsia which can bring on seizures and coma.
Several studies have found this correlation between smoking and the reduced risk for preeclampsia, but the reasons for this association remain unclear. This study adds a piece of information to the puzzle.
In the course of this study, Wikstrom and her research team discovered that out of 600,000 Swedish women who had babies between 1999 and 2006, those who had smoked during their pregnancies cut their risks for developing preeclampsia by one-third to one-half when compared to their nonsmoking counterparts. However, the protective effects of smoking did not extend to those women who used the popular Swedish smokeless tobacco called "snus."
Since snus and cigarettes both contain nicotine, the study findings suggest that the reason for the lowered risk of preeclampsia is not due to nicotine. Wikstrom believes the culprit might be found instead in the byproducts of burning tobacco, for instance, in carbon monoxide. It has been demonstrated that carbon monoxide can lower levels of specific proteins that block the formation of new blood vessels, such as one that is known as sFlt1.
Wikstrom and her team conducted their work under the auspices of the Karolinska Institute, located in Stockholm, Sweden. A report of these findings was published in the American Heart Association journal Hypertension.