Pelvic Venous Insufficiency: How Pelvic Venous Disorders and Pelvic Varicose Veins Connect

Pelvic venous insufficiency means the veins that drain the pelvis are not doing their job. Blood that should flow up towards the heart falls back down or gets held up, and the veins widen. Doctors now group the problems this causes under one name: pelvic venous disorders, or PeVD. This page explains the family as a whole, how its members connect, and where to read more about each one.

What are pelvic venous disorders?

Pelvic venous disorders are a group of conditions affecting the veins of the pelvis, the lower tummy and the tops of the legs. The group includes:

• Pelvic congestion syndrome — long-term pelvic pain from widened, refluxing pelvic veins
• Vulval and vaginal varicose veins — visible veins on the vulva, often linked to pregnancy
• Nutcracker syndrome — the left kidney vein squeezed between two arteries
• May-Thurner syndrome — the left iliac vein squeezed by the artery that crosses it
• Leg varicose veins of pelvic origin — leg veins fed by leaky pelvic veins
• Varicocele — widened veins around the testicle, the male counterpart

For years these were treated as separate conditions with separate names. In 2021, an international group of specialists argued that the old names hid how closely the conditions are linked, and introduced a shared way of describing them. That is why you may now see “PeVD” on clinic websites and in letters.

Pelvic varices and pelvic varicose veins

Pelvic varices are simply varicose veins inside the pelvis. They sit around the womb, ovaries, bladder or bowel, so you cannot see them. Some people call them ovarian varicose veins or varicose veins in the ovary. Strictly, the widened veins are the ovarian veins and the network around the ovary, not the ovary itself.

Pelvic varices are common, especially after pregnancy, and many women who have them feel nothing. They matter when they cause symptoms, such as:

• A dull, heavy or dragging pelvic ache, worse after standing and by the end of the day
• A deep ache during or after sex
• Pain that flares around periods
• Visible veins on the vulva, buttocks or backs of the thighs

These symptoms are covered in detail on our pelvic congestion syndrome symptoms page.

Two ways pelvic veins go wrong: reflux and compression

Almost every pelvic venous disorder comes back to one or both of two problems.

Reflux: valves that leak

The ovarian veins and the branches of the internal iliac veins have small one-way valves. If the valves fail, blood falls back down into the pelvis instead of draining upwards. Pregnancy is the main trigger, because pelvic veins widen a great deal to carry the extra blood and may not shrink back fully. Oestrogen and family history may also play a part. Reflux is the commonest cause of pelvic congestion. Read more about what causes pelvic congestion syndrome.

Compression: a vein squeezed further up

Sometimes the valves are fine but the outflow is blocked. Pelvic vein compression happens at two well-known places:

• The left kidney vein, pinched between the aorta and the artery to the gut. This is nutcracker syndrome. Blood backs up and may escape down the left ovarian vein into the pelvis.
• The left common iliac vein, pressed against the spine by the right iliac artery. This is May-Thurner syndrome. It can cause left leg swelling or a clot, and can also divert blood into pelvic veins.

A vein narrowed by an old clot can do the same thing. Compression on a scan is not always a problem, though. It is often found in people with no symptoms at all.

How the conditions overlap

Because the pelvic veins all connect, a problem in one place often shows up somewhere else.

• Pelvic pain and vulval veins. Leaky pelvic veins can drain out through small “escape points” in the groin and perineum, feeding vulvar varicose veins and veins on the buttocks and thighs.
• Pelvic veins and leg veins. In one UK study, pelvic reflux was a major cause of recurrent leg varicose veins in about a quarter of legs treated after previous surgery. If leg veins keep coming back, pelvic veins may be worth checking.
• Compression and congestion. Nutcracker or May-Thurner compression can be the hidden cause of pelvic congestion in some women. Treating only the leaky veins may then not be enough.
• Women and men. In men, the same reflux in the left testicular vein causes a varicocele. Some specialists describe pelvic congestion as the female version of a varicocele.

So, is pelvic congestion syndrome the same as May-Thurner? No. One describes pain from widened pelvic veins, the other describes a squeezed iliac vein. But one can contribute to the other, which is why specialists look for compression when assessing pelvic congestion.

The SVP classification in plain words

The 2021 system is called SVP, after its three parts. Think of it as a short code that sums up your situation.

• S — Symptoms. What you feel. S1 is kidney-area symptoms such as flank pain or blood in the urine. S2 is chronic pelvic pain. S3 is symptoms outside the pelvis, such as vulval or scrotal pain, painful thigh or perineal veins, or a bursting leg pain on walking.
• V — Varices. Where the widened veins are. V1 is near the kidney, V2 is inside the pelvis, and V3 is outside it, on the vulva, scrotum or legs.
• P — Pathophysiology. Which veins are involved, whether the problem is reflux or blockage, and the cause, such as an old clot or compression.

A letter might say “S2 V2”, which simply means chronic pelvic pain with widened pelvic veins. The system is used alongside CEAP, the older code for leg vein disease. It mainly helps specialists and researchers compare like with like. You do not need to learn it.

How pelvic venous disorders are found

Most people start with a duplex ultrasound, often through the vagina as well as the tummy, ideally with you standing, tilted or bearing down so the veins fill. CT or MR venography can show compression higher up. A catheter venogram gives the most detail and is usually done when treatment is planned. See our guide to the pelvic venous ultrasound and the full diagnosis guide.

Other causes of pelvic pain, such as endometriosis, adenomyosis, fibroids, bowel and bladder conditions, need to be considered too. More than one can be present.

How they are treated

Treatment depends on which veins are involved and whether the problem is reflux, compression or both:

• Reflux is usually treated by closing the faulty veins from the inside, called embolisation.
• Compression may be treated with a stent to hold the vein open, mainly for May-Thurner. Stenting for nutcracker is less established.
• Vulval and leg veins can be treated directly, often after the pelvic source.
• Medicines and self-care help some people, and are often tried first.

The evidence for many of these treatments comes from small studies, and not everyone improves. Our guide to pelvic congestion syndrome treatment compares the options. A Singapore vascular surgeon’s page on causes and risk factors gives another view of how reflux and compression fit together.

When to see a doctor

See a doctor if you have pelvic pain that has lasted for months, pain during or after sex, new veins on the vulva, buttocks or upper thighs, or leg varicose veins that keep coming back. Our pelvic symptom check can help you organise your symptoms before an appointment.

Get urgent medical help for sudden severe pelvic or abdominal pain, heavy vaginal bleeding, fever with pelvic pain, a painful swollen leg, chest pain or sudden breathlessness. In Singapore, call 995 in an emergency.

This article is general information, not personal medical advice. Please speak to a doctor about your own symptoms. How we create our content.