Efficacy of two sperm preparation techniques in reducing non-specific bacterial species from human semen

CONTEXT: Artificial reproductive techniques using seminal preparations with bacteria may cause pelvic inflammatory disease and its sequalae. AIMS: To assess efficacy of two sperm preparation techniques to clear bacteria and the effect of bacteriospermia on sperm recovery rates. SETTINGS AND DESIGN: A descriptive cross-sectional study was carried out among males of subfertile couples. SUBJECTS AND METHODS: Semen samples were randomly allocated into swim-up method (group S, n = 68) and density gradient method (group D, n = 50) for sperm preparation. Seminal fluid analysis and bacterial cultures were performed in each sample before and after sperm preparation. STATISTICAL ANALYSIS: McNemar's chi-squared test and independent samples t-test in SPSS version 16.0 were used. RESULTS: Organisms were found in 86 (72.88%) out of 118 samples, before sperm preparation; Streptococcus species (n = 40, 46.51% of which 14 were Group D Streptococcus species), Coagulase negative Staphylococcus species (n = 17, 19.76%), Staphylococcus aureus (n = 13, 15.11%), Coliform species (n = 11, 12.79% of which 09 were Escherichia coli) and Corynebacterium species (n = 5, 5.81%). There was a statistically significant reduction of culture positive samples in raw vs. processed samples; in group S, 49 (72.05%) vs. 16 (23.52%) and in group D, 37 (74%) vs. 18 (36%). In group S and D, mean (SD) recovery rates of culture positive vs. culture negative samples were 39.44% (SD-14.02) vs. 44.22% (SD-22.38), P = 0.39 and 52.50% (SD-37.16) vs. 49.58% (SD-40.32), P = 0.82 respectively. CONCLUSIONS: Both sperm preparation methods significantly reduced bacteria in semen, but total clearance was not achieved. Sperm recovery rate was not affected by bacteriospermia.