Influence of mitochondrial membrane potential of spermatozoa on in vitro fertilisation outcome.

To determine whether the outcome of in vitro fertilisation (IVF) is influenced by the percentage of spermatozoa with functional mitochondria, a total of 91 random couples undergoing IVF were included. Mitochondrial function was determined by flow cytometry and expressed as percentage of spermatozoa. Conventional sperm parameters were studied by light microscopy. Reproductive outcome parameters were fertilisation rate, embryo quality and clinical pregnancy. It was found that the fertilisation rate was correlated with the percentage of spermatozoa (r = 0.24, P = 0.01) as well as with the percentage of highly motile spermatozoa. However, we did not find any relationship between the percentage of spermatozoa and embryo quality. Nevertheless, no patient who exhibited less than 64% of spermatozoa achieved pregnancy. It is concluded that determination of Δψ(m) provides accurate information to guide physicians to identify male patients for whom IVF will be unlikely to result in pregnancy. Therefore, we suggest that the percentage of spermatozoa may contribute to identify the most appropriate treatment for an individual patient.