Hello, my husband and I have had a total of 6 good/top quality day 5 embryos implanted over the course of 2 years (2021- present). I have endometriosis, which I had surgery for in 2021. Following this surgery we had a successful FET which sadly ended at 5weeks 6 days. All 3 further transfers have been unsuccessful (our latest attempt we transferred 2 embryos). Due to the surgery I now have a diminished ovarian reserve and only one of my ovaries is functioning. We haven’t had any further testing for NK cells or autoimmune issues, so I suppose my question is, what further tests should I look in to having done? I don’t want to start a new cycle at 38 without having further investigations in to why the embryos are not implanting. Is this something you can advise me with?