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How to select ICSI-viable sperm from the most challenging samples

Sperm characteristics are routinely assessed in fertility clinics as decisive factors to select sperm for improved intracytoplasmic sperm injection (ICSI) outcomes. A recent study suggests that, in patients with non-obstructive azoospermia, no specific defect or combination of abnormalities in testicular sperm precluded chance of pregnancy, while also suggesting sperm motility and acrosome defects are the proxies relevant to ICSI outcomes.

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Fig. 1: Machine learning algorithm-based testicular sperm selection.


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Correspondence to Reza Nosrati or David Sinton.

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Nosrati, R., Sinton, D. How to select ICSI-viable sperm from the most challenging samples. Nat Rev Urol 19, 135–136 (2022).

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