That, as they say, is the $64,000 question. Here's what I know about the ovaries, in general. The ovaries produce estrogen and progesterone. Will taking estrogen cause permanent aromatization? It doesn't seem to have permanent effects in MtF transsexuals so I don't know why BO would have permanent effects. I think it is a marketing gimmick on the part of Transfemme.
Does BO work? I just started 4 days ago. I had used PM before, and it took 3000 mg of PM daily for a month for me to bud. I ran out of PM a couple weeks ago or so, and after 2 weeks, my nipples/areolae were no longer sore. I started BO at 500 mg twice daily, and after two doses, my nipples/areolae began to ache again. The only negative I can find is I've had to increase the amount of insulin I use. In male bodies, estrogen increases insulin resistance which tells me BO is doing something.