Total levels, localization patterns, and proportions of sperm exhibiting phospholipase C zeta are significantly correlated with fertilization rates after intracytoplasmic sperm injection

Objective To study the relationship of total levels, localization patterns, and proportions of sperm exhibiting phospholipase C zeta, with fertilization rates after in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Design Laboratory study; controls vs. patients after IVF (n = 27) or ICSI (n = 17) treatment. Setting Fertility center. Patient(s) A total of 44 semen samples, subjected to either IVF or ICSI treatment. Oocyte collection, ICSI or IVF, determination of sperm concentration and motility, and immunocytochemical analyses of phospholipase C zeta (PLCζ). Intervention(s) None. Main Outcome Measure(s) Percentages of sperm exhibiting PLCζ. Result(s) Significant positive correlation between ICSI fertilization rates and total levels, localization patterns, and the proportion (percentage) of sperm exhibiting PLCζ. Total levels, localization patterns, and the proportion of sperm exhibiting PLCζ are correlated with fertilization rates for ICSI, but not for IVF. Conclusion(s) Evaluating total levels, localization patterns, and proportions of PLCζ may represent a useful diagnostic tool for clinical purposes in men for whom IVF is not advised or has previously failed. This clinical study further supports the fundamental role of PLCζ in the oocyte activation process.