Sperm morphology and IVF: Embryo quality in relation to sperm morphology following the WHO and Kruger's strict criteria

Background. The aim of this study was to examine the correlation between sperm morphology and embryo quality/IVF outcome. Methods. The implication of sperm morphology assessment before an IVF cycle was evaluated. A total of 100 IVF couples where the female partner had either tubal factor (n=50) or unexplained infertility (n=50) entered a prospective study, and sperm samples for the actual cycle were assessed according to the strict criteria and WHO criteria. The study was blinded for the technician involved in sperm morphology analyzing. IVF was carried out according to a long down regulation protocol using GnRH/FSH/hCG and ova were inseminated with 200,000 spermatozoa/ml. Embryos were transferred on day 2 post fertilization in a maximum of three embryos. Results. No significant differences were found between the groups regarding age of the female partner (mean=34.3), no. oocytes retrieved (mean=8.5), fertilization (66.5%), pregnancies (pos. S-hCG/transfer 39.6%) or 'Take home baby rate' (birth rate/transfer 30.0%). As to the score of Kruger's strict criteria and the WHO criteria, we found no correlation between this score and cleavage rate, embryo development or pregnancies. The WHO criteria were found to be a better predictor for fertilization rate than the Kruger's criteria (p<0.002). Conclusion. The strict criteria or sperm evaluation according to WHO have no better predictive value for the outcome of routine IVF.