Ultrastructure of tubular smooth endoplasmic reticulum aggregates in human metaphase II oocytes and clinical implications

The presence of large aSERT, showing attainment of the periphery, demonstrated that the cytoplasm is pathologic. The compromised embryo development and implantation was associated with decreased clinical outcomes and newborn malformations. Therefore, oocytes with large aSERT should not be used for embryo transfer.