Pregnancy Blood Clot Risk Lasts Longer Than Believed

New research reveals that the blood clot risk of giving birth lasts twice as long as previously assumed.

Researchers found that women's blood clot risk after delivering a baby lasts for at least 12 weeks.

Previous studies revealed that the chance of blood clot rises during pregnancy and peaks around the time of delivery.

However, the latest study reveals that the risk remains long after delivery. The findings show that women are 10.8 times more likely to suffer a blood clot zero to six weeks after delivery, and 2.2 times more likely seven to 12 weeks after delivery. Researchers noted that women were 1.4 times more likely to suffer blood clots between 13 and 18 weeks. However, this was not a significant increase.

The study showed that the chance of a blood clot returned to normal by between 19 to 24 weeks after delivery.

"While rare, blood clots are a serious cause of disability and death in pregnant and post-partum women, and many members of our research team have cared for young women with these complications," lead researcher Dr. Hooman Kamel, an assistant professor in the Department of Neurology and the Brain and Mind Research Institute of Weill Cornell Medical College in New York City, said in a news release.

"If you have recently delivered a baby, seek medical attention if you develop symptoms such as: chest pain or pressure; difficulty breathing; swelling or pain in one leg; sudden severe headache; or sudden loss of speech, vision, balance, or strength on one side of your body," Kamel added.

The latest study involved data from 1,687,930 women admitted for labor and delivery at a California hospital in 2005-10. Overall, 1,015 women suffered blood clots during the following 1.5 years.

"Clinicians should consider our results when caring for high-risk postpartum patients, such as those with previous clots, or postpartum patients with symptoms concerning for thrombosis," Kamel concluded.

The findings were presented at the American Stroke Association's International Stroke Conference 2014.