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The study included more than 1.6 million women who gave birth at California hospitals between 2005 and 2010. Of these women, about 1,000 women had a blood clot, including some who suffered a stroke, heart attack or deep vein thrombosis from their clot.
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If people experience symptoms such as chest pain, difficulty breathing, swelling or pain in one leg or sudden severe headache, they should seek medical attention, Kamel said. "These should be taken seriously at any time, but specially during pregnancy and postpartum," he said.
The risk of blood clots rises during pregnancy because of an increase in the hormone estrogen and changes in blood-clotting factors. After delivering the baby, hormone levels eventually go back to normal over the following months.
Other conditions can put people at higher risks for blood clots, too. For example, being obese, being treated for cancer, and having heart or lung disease can increase a person's risk for blood clots.
The study was presented today (Feb. 13) at the American Stroke Association’s International Stroke Conference.
Email Bahar Gholipour or follow her @alterwired. Follow us @LiveScience, Facebook & Google+. Original article on Live Science.