There is a new test that can detect mitochondrial errors in embryos, even when 5day embryos appear normal.
This is what Dr Braverman has to say on the subject. Our egg donor had 40 follicles and 30 eggs were retrieved. I feel that perhaps over-stimming damaged the mitochondria in the eggs.
We, at Braverman Reproductive Immunology (BRI), now recognize that other conditions such as Endometriosis, PCOS, Diabetes, Obesity, Autoimmune Disease, as well as EXCESSIVE IVF STIMULATION can also dramatically affect the oocyte quality. In particular, these
conditions affect the mitochondria, one of the key organelles involved
in oocyte quality and necessary for the correct division of the future
embryo (you need normal mitochondria to supply the power for nuclear
division, if mitochondria function is abnormal even a genetically tested
normal embryo will fail to divide correctly and end up as an aneuploid
embryo after transfer).