Oocyte meiotic spindle morphology is a predictive marker of blastocyst ploidy—a prospective cohort study

Oocyte meiotic spindle morphology is a predictive marker of blastocyst ploidy. Normal spindle morphology is positively associated with fertilization, blastocyst quality, and euploidy.

Like Comment
Related Content

Volume 113, Issue 1, Pages 105–113.e1


Liza Tilia, B.Sc., Michael Chapman, M.D., Suha Kilani, Ph.D., Simon Cooke, Ph.D., Christos Venetis, Ph.D.



To evaluate oocyte meiotic spindle (OMS) morphology at intracytoplasmic sperm injection (ICSI) as a predictor of blastocyst ploidy and whether OMS morphology could aid standard morphology-based blastocyst selection.


Prospective cohort study.


In vitro fertilization clinic.


Patients undergoing ICSI cycles with an intention to perform preimplantation genetic testing for aneuploidy (PGT-A) from October 2014 to December 2017.


The OMS was visualized with the use of polarized light microscopy at the time of ICSI and the morphology classified as normal, dysmorphic, translucent, not visible, or in telophase. Blastocyst biopsy for PGT-A was performed on embryos with suitable development.

Main Outcome Measure(s)

The association of OMS morphology with the resulting blastocyst ploidy was evaluated on an “intention-to-treat” (ITT) and an “as-treated analysis” (ATA) basis.


The morphology of 2,056 OMSs were classified. A strong association of OMS morphology with fertilization, cleavage to at least 6 cells on day 3, and good/top-quality blastocyst formation was present. Normal OMS was positively associated with blastocyst euploidy compared with all other OMS types combined, per either ITT or ATA. Even after controlling for female age, blastocyst quality, and developmental stage, the presence of a normal OMS was strongly associated with the probability of blastocyst euploidy.


OMS morphology is a predictive marker of blastocyst ploidy and can potentially aid standard morphology-based blastocyst selection.

Read the full text here.

Fertility and Sterility

Editorial Office, American Society for Reproductive Medicine

Fertility and Sterility® is an international journal for obstetricians, gynecologists, reproductive endocrinologists, urologists, basic scientists and others who treat and investigate problems of infertility and human reproductive disorders. 


Go to the profile of Samuel Santos-Ribeiro
about 2 years ago

Very interesting results from the group of Tilia et al, expanding on their previous work from 2016. In one shot, the authors present interesting hypotheses to justify the frequent occurrence of aneuploid and mosaic embryos in ART. Pending further validation, we may soon have a more robust manner to assess oocyte competence.