I recently completed my 2nd egg retrieval at age 36 and had very different results. I have PCOS (high AMH =15 and many follicles, regular periods, thin/normal BMI ) and respond well to meds. We used 75 Menopur, 100 Gonal F, 25 HGH, Lovenox, Fyremadel, dual trigger with HCG and Lupron. Had 49 retrieved, 25 mature, 19 fertilized and 1 make it to day 5 which was PGT tested and is abnormal. Developed mild OHSS had fluid drained. I was told I had many embryos arrest between days 3-5. My question is why do embryos arrest? Sperm quality is good no known fertility issues with partner. My first egg retrieval was in 2020 I was 34. Had 36 retrieved, 28 mature, 21 fertilized, 5 day 5 and 4 PGT normal. With this cycle I also had many embryos arrest between days 3-5. My second question would be if you have any insight into why my cycle failed? Is age making that big of a difference? I am working with a well known Reproductive Immunologist (due to RIF) so I was on Metformin, Lovenox, Prednisone, many other supplements, diet and life style modifications at least 4 months prior to ER all of which was supposed to support egg quality.