I think your passion to continue breastfeeding is inspiring and want to give you all the encouragement in the world to stick with it.

My (naturally conceived) DD was breastfed until she was a bit over 2yo and I am so proud of her and myself for having that wonderful start to life. She is a healthy, bright and inquisitive 4yo now and I like to attribute some of that to breastfeeding! We now find ourselves TTC#2 and after 2 years of trying (last 12 months on fertility trt), we are now on the IVF journey. I never thought that this would be us! DD was conceived after just 5 months of trying and we never suspected we would have any trouble however, as the months pass I hold firm to the thought that each month is one month closer to a pregnancy and I cherish the time that I have to spend with DD, being constantly amazed as I watch her grow and learn.

I'm not sure if I have any answers for you but if you're passionate about continuing both fertility trt and breastfeeding (I think I would be if I were in your shoes), find someone who can help you do it. Talk to your FS about what you can and can't do, sounds like you can continue to try IUI? Is that an option that you feel positive about? Which particular drugs are a no-no for BF eg. can you express to feed for the first half of collection cycle and then go back to b'feeding after EPU? Can you express enough in advance to feed your bub for the whole EPU cycle (scary thought I know!)? I am constantly amazed by the stories of what people can achieve when they are passionate about making-it-happen and I wish you all the best in your decisions. Where there is a will there is a way ... just keep asking questions.