Glutathione peroxidase activity in seminal plasma and its relationship to classical sperm parameters and in vitro fertilization-intracytoplasmic sperm injection outcome.

OBJECTIVE: To relate the glutathione peroxidase (GPX) activity level in human seminal plasma with standard semen parameters and spermatozoa fertilization potential in terms of fertilization and pregnancy rates in an IVF program.
DESIGN: Prospective study.
SETTING: Human Reproduction Unit at Cruces Hospital (Vizcaya, Spain). PATIENT(S): Three hundred consecutive males from infertile couples participating in the IVF program. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Analysis of GPX activity in seminal plasma by spectrophotometry. RESULT(S): GPX activity in seminal plasma was significantly lower in patients with abnormal sperm as assessed by 1999 and 2010 World Health Organization (WHO) criteria, compared with normozoospermic individuals. There was a more significant decrease in those samples with severe sperm pathologies. GPX values were significantly lower in samples with severe asthenozoospermia, oligozoospermia, and teratozoospermia compared with normal samples. However, there was no correlation between GPX activity in seminal plasma in IVF patients and fertilization rates or pregnancy outcome. CONCLUSION(S): Although seminal plasma GPX activity was related to semen quality according to WHO parameters, such an association was not found with IVF-intracytoplasmic sperm injection (ICSI) outcome, presumably because of the well-known ability of IVF-ICSI procedures to overcome sperm deficiencies in the fertilization process.