I had breast cancer in 1981, with surgery and chemo follow...

I had breast cancer in 1981, with surgery and chemo follow up. I developed ovarian cancer in 2003 with surgery and chemo. During treatments, I had low white blood count. Now, after 5 1/2 years, I still have a low count (around 4). Does this mean my bone marrow is damaged? What will bring the counts up?