From the Guidelines
Pregnancy is the primary cause of increased coagulation in women, specifically hypercoagulability, due to the surge in estrogen levels, which enhances coagulation by increasing levels of clotting factors like fibrinogen and factors VII, VIII, IX, and X while decreasing natural anticoagulants 1. This hypercoagulable state is an evolutionary mechanism thought to reduce hemorrhage at the time of childbirth or pregnancy loss, but it also increases the risk of venous thromboembolism (VTE) by 4-6 times during pregnancy, with the greatest risk in the post-partum phase 1. Some key factors that contribute to hypercoagulability in women include:
- Estrogen, which increases levels of clotting factors and decreases natural anticoagulants
- Pregnancy, which induces hypercoagulability due to increased coagulation factor levels and decreased free protein S
- Hormonal contraceptives containing estrogen, which elevate clotting risk by 3-6 times
- Menstruation, which increases coagulation to control bleeding
- Family history of clotting disorders, which may increase the risk of hypercoagulability Women at high risk of hypercoagulability may benefit from preventive measures like low-dose aspirin or heparin during high-risk periods, but these should only be used under medical supervision 1. It is essential for women to be aware of these natural tendencies toward increased coagulation, particularly during pregnancy, while using hormonal contraceptives, or if they have other risk factors like family history of clotting disorders, and to seek medical attention if they experience warning signs of problematic blood clots, such as swelling, pain, or redness in the legs; sudden shortness of breath; or chest pain 1.
From the Research
Hypercoagulability in Women
- Hypercoagulability, or an increased tendency to form blood clots, can be caused by various factors, including hormonal changes, pregnancy, and the use of certain medications 2.
- Women of reproductive age are at a higher risk of developing hypercoagulability due to the use of hormonal contraceptives, pregnancy, and childbirth 2.
- The risk of hypercoagulability can be managed through the use of anticoagulant medications, such as low-molecular-weight heparin and warfarin, as well as lifestyle changes, such as maintaining a healthy weight and avoiding smoking 3, 4.
Risk Factors for Hypercoagulability
- Hormonal changes, such as those that occur during pregnancy and childbirth, can increase the risk of hypercoagulability 2.
- The use of hormonal contraceptives, such as combined oral contraceptives, can also increase the risk of hypercoagulability 2.
- Other risk factors for hypercoagulability include a family history of blood clots, obesity, and smoking 3, 5.
Management of Hypercoagulability
- Anticoagulant medications, such as low-molecular-weight heparin and warfarin, are commonly used to manage hypercoagulability 3, 4.
- New oral anticoagulants, such as direct thrombin inhibitors and factor Xa inhibitors, have also been developed and are being used to manage hypercoagulability 6.
- Lifestyle changes, such as maintaining a healthy weight and avoiding smoking, can also help to manage the risk of hypercoagulability 5.