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Updated: Oct 9, 2026

Human Egg Maturity Assessment and Its Clinical Application
Published on: August 19, 2019
The spindle observation and its relationship with fertilization after intracytoplasmic sperm injection in living
W H Wang1, L Meng, R J Hackett
1Division of Reproductive Medicine and Infertility, Department of Obstetrics and Gynecology, Women and Infants Hospital of Rhode Island, 101 Dudley Street, Brown University School of Medicine, Providence, Rhode Island 02905-2499, USA.
Objective:
To image spindles in living human oocytes and to examine the relation between spindles and fertilization after ICSI.
Design:
The LC polscope was used to examine spindles in an observational study of living oocytes.
Setting:
Academic IVF clinic.
Patient(S):
Women being treated for infertility.
Intervention(S):
Oocytes retrieved from patients for infertility treatment were examined before ICSI. Aged, unfertilized oocytes after IVF or ICSI were examined with polscope and confocal microscopes to compare the two methods.
Main Outcome Measure(S):
Spindle structure in living oocytes and fertilization after ICSI.
Result(S):
Spindles could be imaged in 61.4% of oocytes. More oocytes with spindles than oocytes without spindles fertilized normally after ICSI (61.8% vs. 44.2%). Spindles in most aged oocytes were partially or completely disassembled, and only a few microtubules around the chromosomes or dispersed microtubules in the cytoplasm were observed. Confocal images of immunostained spindles were almost identical to polscope images of spindle birefringence.
Conclusion(S):
Spindles in living human oocytes can be imaged by using the polscope. A birefringent spindle in human oocytes may clinically predict the quality and age of oocytes. This method also can be used to monitor spindle position during ICSI.
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