Welcome to Connect, @sunbird09 Over time, some people with PV may develop MF. This occurs if scar tissue replaces bone marrow which can interfere with the bone marrow’s ability to produce enough healthy blood cells.

Here’s another link to a good discussion in the forum with members who have MF. You can reverse the order of the conversations to see the most current replies.
Do you know if you have a genetic mutation such as JAK2?

~Myelofibrosis w/ JAK2 mutation
https://connect.mayoclinic.org/discussion/myelofibrosis-w-jak2-mutation/
Where you on any treatment plan for your PV? What has your hematologist oncologist suggested for this next phase of your condition?

Like you, I was initially diagnosed with PV about 6 years ago. My Doctor, at the time, prescribed Hydroxyurea but I was not able to tolerate the drug. Another bone marrow aspiration was ordered and the diagnosis was changed from PV to Myelofibrosis. I changed doctors and for three years I took no drugs; the doctor just monitored my blood counts. However, platelets started to rise and two years ago I started Jakafi ... I just turned 74. The drug worked for me but my HBC is low, causing fatigue. My doctor wants me to consider changing from Jakafi to Ojjaara. Ojjaara has helped some patients improve hemoglobin levels.
We shall see, best of luck to you.

The local clinic (Sarah Cannon) is closing so I am changing doctors again. Will discuss the suggested change in drug treatment with new doc. I have good and bad days ... sunshine and mild weather helps.