Vein
A vein is a blood vessel that carries oxygen-poor blood back to the heart. Veins often have valves that help the blood flow back against gravity.

Symptoms rather than terms?
Describe what's going on — we'll find the right doctor for you.
A vein is a blood vessel that carries oxygen-poor blood back to the heart. Veins often have valves that help the blood flow back against gravity.

Symptoms rather than terms?
Describe what's going on — we'll find the right doctor for you.