May-Thurner Syndrome (MTS) is a vascular compression disorder that, while underdiagnosed, can lead to serious complications if left untreated.

With growing awareness and medical advances, patients now have more information and treatment options than ever before. 

What Is May-Thurner Syndrome?

May-Thurner Syndrome is a condition in which the left iliac vein is compressed by the overlying right iliac artery, leading to reduced blood flow from the left leg.

This compression can cause chronic venous insufficiency, swelling, pain, and in severe cases, deep vein thrombosis (DVT).

Although often asymptomatic at first, this condition can silently cause long-term complications. With increasing knowledge among healthcare providers, May-Thurner is now more commonly identified and effectively managed.

MT Syndrome Causes

Understanding what causes May-Thurner Syndrome requires a closer look at anatomy. The root issue lies in the positioning of the right common iliac artery as it crosses the left common iliac vein.

The resulting compression restricts venous return and can eventually irritate the vein walls, leading to thickening or even clot formation.

Is May-Thurner Syndrome Genetic or Acquired?

One of the most commonly asked questions is:

Are people born with MT Syndrome?

While the anatomical layout is congenital, not all individuals born with this vein-artery configuration will develop symptoms. External factors such as pregnancy, extended sitting, trauma, or surgery can trigger symptom onset in predisposed individuals.

Symptoms of MTS

Symptoms typically affect the left leg and may include:

• Chronic leg swelling (especially by day’s end)
• Leg pain or heaviness
• Skin discoloration
• Formation of varicose veins
• Pain after long periods of sitting or standing
• Increased risk of DVT

What Causes Venous Compression Syndrome?

Venous Compression Syndrome, a broader category that includes May-Thurner, is caused when external structures press against a vein, restricting blood flow.

In the case of MTS, it’s the right iliac artery compressing the left iliac vein.

This mechanical pressure increases the risk of venous hypertension, clots, and chronic inflammation, especially when left untreated.

Who Is Most at Risk?

• Women aged 20–50 (especially post-pregnancy)
• People with sedentary lifestyles or desk jobs
• Patients with a history of DVT
• Individuals undergoing pelvic or orthopedic surgery
• Long-distance travelers or those on prolonged bed rest

These factors may trigger or worsen the condition, which is why early detection and preventive care are crucial.

Can May-Thurner Syndrome Go Away on Its Own?

A commonly asked question is:

Can MTS go away?

The honest answer is: rarely. While mild compression may remain asymptomatic, once symptoms begin—especially if DVT occurs—the condition usually requires intervention.

Modern treatments such as angioplasty, stenting, and blood thinners offer effective relief and long-term management, but the anatomical compression itself does not spontaneously resolve.

Treatments in May-Thurner Syndrome

Thanks to advances in interventional radiology and vascular imaging, MTS can now be diagnosed non-invasively using:

• CT Venography
• MR Venography
• Intravascular Ultrasound (IVUS)

Once diagnosed, treatment is typically aimed at restoring proper venous flow, and may include:

• Balloon angioplasty
• Venous stent placement
• Anticoagulation therapy
• Compression stockings
• Lifestyle modifications (e.g., elevating legs, staying active)

Final Words

Living with MTS is entirely possible thanks to early diagnosis, tailored treatments, and ongoing support.

If you’re experiencing unusual leg swelling, discomfort, or have a history of DVT, it’s worth speaking to a vascular specialist. With the right strategy, individuals can return to daily life with improved comfort, reduced risk, and better vascular health.

Frequently Asked Questions 

What is the cause of May-Thurner Syndrome?

It is caused by the compression of the left iliac vein by the right iliac artery, leading to blood flow restriction and vein wall damage.

Are people born with MT Syndrome?

While people may be born with the anatomical layout that predisposes them to it, not all develop symptoms unless triggered by environmental or health factors.

What causes Venous Compression Syndrome?

Venous compression results from external pressure on veins, most commonly from adjacent arteries or masses, causing poor circulation and vein inflammation.

Can MTS go away?

No, the physical compression remains unless corrected by medical procedures. However, symptoms may be managed effectively with treatment.