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

Artificial reproductive techniques using seminal preparations with bacteria may cause pelvic inflammatory disease and its sequalae.

To assess efficacy of two sperm preparation techniques to clear bacteria and the effect of bacteriospermia on sperm recovery rates.

A descriptive cross-sectional study was carried out among males of subfertile couples.

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.

McNemar's chi-squared test and independent samples t-test in SPSS version 16.0 were used.

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.

Both sperm preparation methods significantly reduced bacteria in semen, but total clearance was not achieved. Sperm recovery rate was not affected by bacteriospermia.