Pelvic congestion syndrome – including iliac vein compression (May Thurner) and ovarian vein incompetence

Pelvic congestion syndrome relates to a combination of symptoms and signs seen in women associated with high pressure in the venous system in the pelvis. Raised venous pressure in the pelvis is caused by one of two conditions: those being ovarian vein incompetence and iliac vein compression (May-Thurner syndrome).

Ovarian vein incompetence

Which is related to (usually the left) ovarian vein which should be draining blood out of the pelvis up to the main veins draining into the heart. The ovarian vein has valves which should allow flow only in one direction and that direction is from the pelvis up towards the chest. In some women, these are not working, and the direction of flow in the ovarian vein is from the upper abdomen down into the pelvis causing congestion in the veins of the pelvis.

Iliac vein compression (May-Thurner Syndrome)

The 2nd cause of pelvic vein syndrome is where the veins draining the legs become compressed or squashed in the pelvis. These are the iliac veins, and it is usually the left side which can be squashed between an artery and the spine. This makes it difficult for blood to drain from the leg through the pelvis back to the upper abdomen and heart. The pressure in the venous system in the pelvis rises resulting in pelvic venous congestion. This condition is called iliac vein compression or pelvic venous compression.  Sometimes it is called May Thurner syndrome.  Compression is relatively common. It is seen in between 20 and 25% of people and is more common in women than in men. Most people do not have any problems related to it, but the percentage that does have problems is not known.  It has been recognised for many years (first described by May and Thurner in 1957) but the diagnosis has been difficult to make. More recently, there are ultrasound protocols designed to make the diagnosis. Other diagnostic tools include venogram, magnetic resonance venography and intravascular ultrasound.

What are the symptoms?

There are many conditions which can give rise to pelvic aching and discomfort, one of which is pelvic congestion syndrome. In women, the obstructed flow through the iliac veins, or the engorgement related to ovarian vein incompetence may lead to heavy menstrual flow; heaviness or dragging pain in the pelvis; heavy feeling in the legs and thighs or hips; back pain; pain on intercourse (dyspareunia); pain or discomfort when passing urine.  Both iliac vein compression and ovarian vein incompetence can lead to chronic venous insufficiency including varicose veins.  They can also be a cause of recurrent varicose veins.

What are the treatment options?

Treatment of pelvic congestion syndrome depends on the exact cause. If the cause is iliac vein compression, then treatment can be conservative, or one could consider iliac vein stenting. If the cause is incompetence of the ovarian vein, then blocking the vein using coils prevents the transmission of pressure and decreases the congestion of the veins in the pelvis.


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