Hello Dr.,
I am currently 36 with unexplained infertility. We sought help in 2019 and ended up with a successful IVF cycle, 7 PGS -tested normal embryos (1 day 5 and 6 day 6). We transferred our day 5 embryo with no issues in 2020 and he was born healthy via vaginal delivery in May 2021. This past summer we were ready to implant our next embryo. My doc did a hysteroscopy to make sure everything looked good, and it did! We did the same protocol as my first FET: lupron, estrogen, aspirin. My lining never got thicker than 6mm despite my estrogen levels rising to the thousands. My doc even added Viagra suppositories, but my lining “collapsed” to 5mm and the cycle was cancelled. We then tried a natural cycle. Things were growing slowly, I got to 7.3mm and we were going to give it one more day prior to triggering since I hadn’t ovulated yet. Unfortunately, the next day, my lining collapsed again to 5mm and the cycle was cancelled. Any insight on what could be the problem? I’ve read through some of your previous posts, but I don’t fit any of those criteria, as far as I can tell. My lining with my first FET got to 9mm. Is there something I/we are missing?

I appreciate your help and this forum!