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These Two Things Raise a Women’s Blood Clot Risk

Deep Vein Thrombosis (DVT) is a condition that develops when a blood clot forms in the deep veins of your legs. As it circulates through them, there is a risk that the blood clot will break free and become lodged in your lungs (pulmonary embolism), which is a potentially fatal complication.

When pregnant women develop clots in the deep veins of their legs, groin or arms, the condition is called Venous Thromboembolism (VTE). While the name is different, the danger to your lungs is the same, which is why VTE during pregnancy and post-partum is one of the leading causes of maternal deaths.

What We Know About VTE Varicose Veins & Pregnancy: What You Need to Do (and Why You Shouldn’t Worry)

Until recently, only a few VTE risk factors had been identified. During pregnancy these included:

  • A previous episode of VTE
  • A relative with a previous VTE episode
  • Advanced maternal age
  • Smoking
  • High BMIs
  • In-vitro fertilization

For post-partum VTEs, risk factors included:

  • Emergency c-sections
  • Still births
  • Pre-eclampsia (high blood pressure during pregnancy)
  • Varicose veins 
  • Post-partum infection

New VTE Risk Factors Identified

Now, thanks to a study in Japan, two new VTE risk factors have been identified: Endometriosis and recurring miscarriages.  To reach these findings, the study authors reviwed data from 103,070 pregnant Japanese women, collected between January 2011 and March 2014. Participants completed questionnaires in their first, second and/or third trimester, and their medical records were then transcribed immediately after delivery and one month post-partum.

First, researchers found that the frequency of VTE in the Japanese population was 7.5 per 10,000 pregnancies during both the pregnancy and post-partum period.

After identifying previous known risk factors, and adjusting for their presence, researchers were able to discover two new predictors for VTE: the presence of endometriosis and recurrent pregnancy loss. Women with endometriosis were 2.7 times more likely to develop VTE; women with multiple miscarriages had a risk factor that was 6.13 times higher.

Pregnancy with VTE Risk Factors

Knowing your risk for VTE is important, since pregnant women with one or more predictors may need to take precautionary measures. In fact, VTE is such a dangerous complication, at-risk pregnant women may need to take anti-coagulants (with the supervision of and recommendation from their physicians.) To learn more about managing VTE and other venous conditions, schedule a consultation with our Houston vein specialists.

Sources: Thieme, the Journal of Thrombosis and Haemostasis