What's this test for?

This test is ideal if you're experiencing an unexplained abnormal clotting lab result, specifically a prolonged aPTT, and need to figure out why. It helps identify whether Factor XII deficiency is the cause, since this deficiency doesn't cause bleeding or clotting problems on its own but can show up as an odd lab finding. It's often used to rule out other more serious clotting disorders.

How should I prepare for this test?

How can I naturally support healthy blood clotting function? Staying well hydrated and eating a balanced diet with adequate vitamin K (found in leafy greens) supports normal clotting protein production. Regular movement and avoiding excessive alcohol also help keep your blood's clotting system working properly. That said, Factor XII deficiency itself isn't something diet or lifestyle changes can fix, since it's typically an inherited trait.

What's included in this test?

This test measures how well Factor XII, one of the proteins involved in the blood clotting process, is functioning. Checking this specific factor helps pinpoint whether a clotting pathway abnormality picked up on other tests is coming from this particular protein rather than a more clinically significant one.

What happens after I get my results?

Your Factor XII activity level will appear in your account along with the normal reference range so you can see exactly where your result falls. If your level is low, the report explains what that means, and typically no lifestyle changes are needed since Factor XII deficiency doesn't raise your risk of bleeding or clots. You can download the standard lab report anytime from your account, and if you retest in the future, the trends feature lets you track your levels side by side.

When will I get my results?

Results for this test are typically ready within about 7 days of your sample being collected at the lab. You'll get a notification as soon as your results are posted to your account, where you can view and download the full report.

Who should consider this test?

This test is a good fit for anyone who received a lab result showing a prolonged aPTT (a common clotting screening test) without any bleeding symptoms. It's also useful for people being evaluated before surgery when a routine clotting screen came back abnormal. Since Factor XII deficiency is often discovered incidentally, this test helps confirm that's the explanation rather than something more concerning.

What symptoms indicate I may need this test?

Factor XII deficiency itself doesn't cause symptoms since it doesn't lead to bleeding or clotting problems. Most people find out they need this test after a routine blood clotting screen (aPTT) comes back prolonged during a pre-surgery workup or unrelated lab panel. If you've been told your clotting screen looks unusual but you have no bruising or bleeding issues, this test can help explain why.

What is Factor XII and why does it matter?

Factor XII is one of several proteins in your blood that work together in a chain reaction to help blood clot when needed. It matters mainly because low levels of it can throw off a common clotting screening test (the aPTT) even though it doesn't actually cause bleeding or clotting issues. Understanding your Factor XII level helps clarify confusing lab results and avoid unnecessary worry or additional testing.

What does low Factor XII activity mean?

A low Factor XII level usually just means you have a mild, inherited difference in this particular clotting protein. It's generally harmless and isn't linked to bleeding easily or to forming dangerous clots. Most people with low Factor XII never need any treatment or ongoing monitoring.

What causes low Factor XII levels?

Low Factor XII activity is most often inherited, meaning it runs in families and has been present since birth. Certain blood thinners, like direct thrombin or factor Xa inhibitors, can also cause falsely low readings on this test, which is why it's best to avoid those medications for a few days before testing if it's safe to do so. Warfarin, on the other hand, does not affect Factor XII results.

Getting your blood test with us is easy, private & backed by the power of science.Long story short: In the test options, use the filters or search box to narrow your choices and find the test you want. If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test. Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout. If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want. When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system. Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way. You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy! If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.

How do I know which test to get?

In the test options, find the test you want. If you’re not sure which test to get, we can lend a hand in finding the right option. Just text or call us at 754-799-7833, email us at support@privatemdlabs.com, and we'll gladly help you. We've got your back and reply quickly.

When will my lab results be available?

Most test results will be available within 1–3 business days. Once they're ready, we'll send an email and text message to let you know. After your blood draw, just hang tight and don't worry – we'll keep you updated and in the loop! If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com, and we'll gladly help you.

Is it possible to make changes to my lab order if I made a mistake with the name, date of birth, or any other details?

Absolutely! We totally understand that errors can happen. No worries, we're here to help you. Just reach out to us via text at 754-799-7833 or shoot us an email at support@privatemdlabs.com. Remember to include your order number and let us know the correct information you’d like to update. Our awesome team will jump right in and make sure everything is sorted out and accurate for you. There are no changes necessary if your address is wrong on the requisition though. We don’t mail anything out. Our lab requires an address to be listed to generate an order.

Do you accept health insurance?

Only HSA & FSA is accepted. Our services are strictly self-pay and cannot be submitted to your health insurance provider except for Health Savings Accounts or Flexible Savings Accounts. This policy applies to all insurance companies, including federal health insurance programs like Medicare. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com.

Can I cancel my order?

Yes. We get it – sometimes your needs change. As long as your samples haven’t been collected yet, we’re happy to help you cancel your order. If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com. You can read more about our cancellation policy here.

How can I find a lab location near me?

During the ordering process, you’ll be able to select a specific lab near you, with no strings attached! You can switch it up later easily and visit any of our authorized locations as long as it’s the same lab company you selected your test for (Quest Diagnostics or Labcorp). Before you proceed with your order, feel free to browse through all our lab locations here. This will give you the peace of mind of knowing that there's a lab nearby your home, office or your favorite gym. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.

Factor XII Activity Test - Clotting Factor Check

Getting your blood test with us is easy, private & backed by the power of science.

Long story short:

In the test options, use the filters or search box to narrow your choices and find the test you want.
If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test.
Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout.
If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want.
When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system.
Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way.
You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy!

754-799-7833

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