Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Health & Pregnancy

Font Size

Pregnancy and the Increased Risk of Developing Blood Clots - Topic Overview

Pregnant women have a higher risk of deep vein thrombosis and pulmonary embolism.1

What raises the risk of blood clots during pregnancy?

The three main risk factors (things that increase risk) for developing deep vein thrombosis and pulmonary embolism are abnormal clotting, reduced blood flow, and damage to the veins. These risks are all higher during pregnancy, most likely because of:

  • Changes in hormone levels and blood composition that influence clotting.
  • Reduced blood flow in the legs due to the weight of the fetus pressing upon veins.
  • Injury to veins during delivery or surgery.
  • Inactivity after cesarean section surgery or delivery.

Women who are obese, are older than 35, or have a family or personal history of blood clots have a higher risk of developing a clot that can lead to pulmonary embolism.

After delivery, the risk for blood clots is higher than during pregnancy. This risk usually returns to normal after a few weeks after delivery.2

If a woman has a cesarean section, she is even more likely to develop one or more of these clots.

Who is screened for risk of blood clots?

Women with the following history may be screened for genetic factors that can increase the risk of forming blood clots:

How are blood clots prevented?

For pregnant women who are more likely to develop blood clots, several methods may be used to prevent deep vein thrombosis and pulmonary embolism. These include:

How are blood clots treated?

A pregnant woman who is diagnosed with deep vein thrombosis or pulmonary embolism will work with her doctor to decide which anticoagulant medicine to take during pregnancy. She may take heparin, because it has not been shown to affect the fetus.

After delivery, the woman might take another anticoagulant, such as warfarin, for a few weeks or a few months.

    WebMD Medical Reference from Healthwise

    Last Updated: September 09, 2014
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
    Next Article:

    Pregnancy and the Increased Risk of Developing Blood Clots Topics

    Today on WebMD

    hand circling date on calendar
    Track your most fertile days.
    woman looking at ultrasound
    Week-by-week pregnancy guide.
    Pretty pregnant woman timing contaction pains
    The signs to watch out for.
    pregnant woman in hospital
    Are there ways to do it naturally?
    slideshow fetal development
    pregnancy first trimester warning signs
    What Causes Bipolar
    Woman trying on dress in store
    pregnant woman
    Close up on eyes of baby breastfeeding
    healthtool pregnancy calendar
    eddleman prepare your body pregnancy