I'm so sorry for your loss.
I was reading an article about a woman who lactated for 2 yrs after a m/c. I think they were saying she may have elevated prolactin levels. It may go away after a certain point in the pregnancy.
I've been lactating as well, but it's only 1 month past my m/c. Engorgement isn't fun, is it? I went from a b-cup to a d-cup overnight.
I agree with the others, if it's bothering you please see a doc.