I'm not in this position so I don't have any medical/scientific knowledge to draw on but I would think that Tamoxifen should be putting a stop to the ovaries and oestrogen production that is essential to pregnancy. I don't know how long you're on Tamoxifen for though and would imagine that you could become pregnant once you go off it. I guess the only surety you can have is to have the ovaries removed. But, please remember, I'm not speaking from a position of real knowledge or experience. Best to discuss the matter with your medical team.
