Real-time artificial-intelligence-assisted rare sperm searching: a prospective, multicentre, paired sister-oocyte pilot study

RESEARCH QUESTION: In severe male factor infertility, does real-time artificial intelligence (AI)-assisted sperm searching reduce search time and increase sperm recovery compared with unassisted searching, and does its use affect downstream embryological outcomes? DESIGN: This was a prospective, multicentre, within-patient paired split-dish pilot study (January 2024-September 2025). Matched dishes containing processed testicular tissue or semen from poor-prognosis non-obstructive azoospermic (NOA) or severe oligozoospermic patients (n = 40) were searched with and without AI assistance. Primary outcomes were time per spermatozoon and time per dish, reported as median (IQR) because distributions were skewed and included zero values. Secondary outcomes were spermatozoa recovered per dish and, in the subset with oocytes injected from both conditions, fertilization and utilizable embryos per mature oocyte injected. RESULTS: Median time per dish decreased from 35.80 min (IQR 27.85-44.75) to 21.80 min (IQR 18.00-29.88) with AI assistance (P < 0.0001; 40 paired comparisons). Median spermatozoa recovered per dish increased from 0.00 (IQR 0.00-3.50) to 0.75 (IQR 0.00-5.00) (P < 0.0001). In 18 patients where spermatozoa were found with both methods, median time per spermatozoon decreased from 10.85 min (IQR 6.95-38.65) to 5.50 min (IQR 2.27-11.00) (P = 0.001). Intracytoplasmic sperm injection proceeded using spermatozoa identified with AI assistance alone in eight of 40 cases. In a small subset of patients with oocytes injected from both conditions (12 paired patients), an exploratory analysis showed that the median fertilization rate increased from 0.0% (IQR 0.0-43.8) to 36.7% (IQR 21.2-63.9) (P = 0.039), and utilizable embryos per metaphase II oocyte increased from 0.00 (IQR 0.00-0.15) to 0.21 (IQR 0.15-0.31) (P = 0.02). CONCLUSIONS: AI-assisted sperm localization reduced search time and increased sperm recovery in paired within-patient comparisons. Embryological findings from a small subset are exploratory and larger studies are required for confirmation.