Polycythemia verais a blood disorder in which your body makes too many red blood cells.

Over time, serious complications can occur.

The condition develops slowly.

Early stage polycythemia vera can cause fatigue

10'000 Hours / Getty Images

The average age at diagnosis is 60, although it can affect people younger than 40 years old.

Red blood cells carry oxygen to the cells of the body to provide them with energy.

Worsening symptoms can be a sign that polycythemia is progressing.

If you have been diagnosed with polycythemia vera, your doctor may check for complications with periodic blood tests.

Treatment for polycythemia vera can reduce the risk of complications for the person giving birth and the baby.

Blood clots in the veins or arteries and bleeding anywhere in the body can cause a range of symptoms.

The symptoms differ depending on which area of the body is affected.

Summary

Polycythemia vera often has vague symptoms or no symptoms early in its course.

It usually progresses slowly, and you may notice dizziness, fatigue, headache, and other symptoms.

Over time, serious complications can occur, including blood clots and blood cancer.

A Word From Verywell

Polycythemia vera is a lifelong condition.

You should learn to recognize signs of worsening disease or complications.

National Organization for Rare Disorders.Polycythemia vera.