During pregnancy, more blood pumps through your body to meet the needs of your developing baby. More blood flowing through the body means added pressure on your blood vessels, which can cause them to narrow. This, along with hormonal changes, can make you five times more likely to have a blood clot during pregnancy or right after delivery than someone who is not pregnant.

Some blood clotting disorders, such as antiphospholipid syndrome (APS), can raise this risk of blood clots during pregnancy even more, which can cause pregnancy-related problems like miscarriage or preeclampsia (high blood pressure during pregnancy). This is especially true if you have a history of blood clots.

Talk with your doctor if you have APS and are pregnant or planning to become pregnant. People who have APS can have successful pregnancies. Your doctor may suggest medicines to prevent blood clotting as well as scheduling more tests such as sonograms to check the baby’s growth.

Blood clotting disorders and pregnancy prevention

If you are trying to prevent pregnancy, talk to your doctor about birth control. Birth control with estrogen can raise your risk of blood clots. Some examples of contraception without estrogen include:

• Intrauterine devices (including those with progestin)
• Progestin-only pills or implants
• The barrier method

Some people with blood clotting disorders may never get blood clots and may not need treatment. Your doctor will consider your previous history of blood clots as well as your current risk factors to decide a treatment plan.

How are blood clotting disorders treated?

If you have a history of blood clots, your doctor may prescribe blood thinners. You may take blood thinner medicine by mouth (such as warfarin or aspirin) or as a shot (such as heparin). Side effects of warfarin and heparin include heavy bleeding, severe headaches, and dizziness. Warfarin also can interact with over-the-counter medicines such as cold or allergy medicines or ibuprofen.

Blood thinning medicine is all about balance. Your doctor will test your blood often to make sure the dose of medicine is correct and your blood has the proper balance between bleeding and clotting.

A group of medicines called direct oral anticoagulants (DOACs) may be an alternative to warfarin or aspirin for some people, as they are safe and effective at preventing blood clots and do not require frequent blood testing. However, you may have to take more doses (twice daily compared to once a day for warfarin). DOACs are most often used in patients with low-risk, inherited blood clotting disorders (such as Factor V Leiden and Prothrombin G20210A). Talk to your doctor about whether DOACs may be right for you.

How do blood clotting disorders affect your health?

It is important to know the causes and risk factors that may increase your chances of developing dangerous blood clots. It is important to get regular checkups and look out for the symptoms of blood clots. If left untreated, blood clots can cause serious problems, including:

• Deep vein thrombosis, or a blood clot in the leg
• Pulmonary embolism, or a blood clot that travels to the lung
• Heart attack
• Stroke

Reference

National Institute of Health (2023) Blood Clotting Disorders Pregnacy and Blood Clots. Retrieved from:  https://www.nhlbi.nih.gov/