Women with preeclampsia have dangerously high blood pressure, thought to be caused by narrowed blood vessels. If not treated, the condition can develop into eclampsia and can kill both the mother and the fetus. However, since delivery almost always resolves preeclampsia, doctors often deliver the infant early.
In his study, Carl van Walraven, MD, with the Ontario Ministry of Health, compared about 13,000 women admitted to the hospital with preeclampsia with more than 284,000 with no history of preeclampsia. All women were followed for up to three years after leaving the hospital.
He found venous thromboembolism -- blood clots -- to be more common in the preeclampsia group. Women with preeclampsia were more than twice as likely to be admitted to the hospital with blood clots during the study period, he reports.
The risk of blood clots in women who have had preeclampsia is still very small, Walraven says.
He says the risk is too small to warrant blood clot prevention to women who have had preeclampsia. But he does suggest that these women become familiar with the symptoms of a blood clot so they can seek immediate medical care.