Assessing Egg Quality in IVF
In the field of assisted reproductive technologies (ART) viable embryos are correlated with good quality gametes. However, tools to assess the viability of oocytes have been limited to subjective morphological criteria such as gross cytoplasmic dysmorphisms, oolemma elasticity and oocyte shape.
New data suggest that CRi’s Oosight system provides more robust and accurate markers of oocyte quality by enabling visualization and quantitation of spindle and inner zona pellucida morphology. CRi’s patented technology can measure misalignment of either microtubules in the spindle apparatus or glycoproteins in the zona that indicate compromised morphology. For example, Figure 1(B) shows a spindle apparatus that is severely disrupted from the normal barrel-shape shown in 1(A), indicating a greater potential for aneuploidy. In addition, measurements using the Oosight system have been shown to correlate with the likelihood of successful blastocyst development and pregnancy (Raju et al. 2007). According to a multi-center trial, pregnancy is 8 times more likely with a well-ordered zona pellucida as measured using the Oosight system (Shen 2005).
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Figure 1. Oosight images showing normal (A) versus abnormal (B) microtubule alignment within the spindle apparatus. Red vectors indicate the long axis of the spindle's microtubules as revealed using Oosight.
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Rama Raju, G.A.; Prakash, G.J.; Krishna, K.M.; Madan, K. Reproductive BioMedicine Online, 14(2):166-174(2007) .
Shen Y, Stalf T, Mehnert C, De Santis L, Cino I, Tinneberg HR, Eichenlaub-Ritter U., Reproductive BioMedicine Online, 2(6):737-51 (2006)
