The effect of sperm morphology and testicular spermatozoa on embryo quality
Objective: To determine the correlation between sperm morphology groups (strict criteria) and testicular spermatozoa, and day 2 and 3 embryo quality in intracytoplasmic sperm injection (ICSI) and in vitro fertilisation (IVF) cases. Methods: A retrospective study was done of 2 402 IVF and ICSI-fertilised embryos classified as good-quality embryos (GQEs) or poor-quality embryos (PQEs). Sperm morphology (strict criteria) was classified as teratozoospermia (P-pattern (< 5% normal); G-pattern (5 - 14% normal)), normozoospermia (N-pattern (> 14% normal)), and testicular spermatozoa (immature, only ICSI group). Results: Sperm morphology (P, G, and N-patterns) and immature testicular sperm had no effect on day 2 or 3 embryo quality for ICSI (p = 0.82) and IVF-fertilised (p = 0.64) embryos, A significant increase in GQEs from day 2 to 3 in the P-pattern group (33 - 39%, p = 0.002) and testicular spermatozoa group (30 - 35%, p = 0.014) was found in ICSI cases. Conclusion: Morphology of human spermatozoa according to Tygerberg's strict criteria and testicular spermatozoa had no predictive value for the outcome of day 2 and 3 embryo quality.