Re-evaluation of the value of sperm morphology in classical in vitro fertilization in a Northeastern Chinese population

OBJECTIVE: This study aimed to re-evaluate the clinical value of a 4% cut-off threshold of sperm morphology in in vitro fertilization (IVF) in a cohort of a Northeastern Chinese population. METHODS: A total of 375 IVF cycles that met strict inclusion criteria were included. These cycles were conducted with semen analysis and oocyte fertilization. A total of 188 embryo-transferred cycles proceeded. According to sperm morphology, 375 cycles were divided into group 1 (329 cycles, <4% normal sperm morphology rate [NSMR]) and group 2 (46 cycles, ≥4% NSMR), and 188 transferred cycles into group A (151 cycles, < 4% NSMR) and group B (37 cycles, ≥4% NSMR). RESULTS: The fertilization and normal fertilization rates were significantly lower in group 1 than in group 2. The normal fertilization rate was significantly correlated with an NSMR < 4% or ≥4%, but the fertilization rate was not significantly correlated with the NSMR. No significant differences were found in pregnancy outcomes between groups A and B. CONCLUSIONS: This study suggests that infertile patients with an NSMR < 4% are more likely to have a poor normal fertilization status in IVF.