Sperm washing and swim-up technique using antibiotics removes microbes from human semen.

Pelvic infections may follow intrauterine or intratubal insemination with washed semen. In this study, we determined whether sperm washing removes microorganisms from human semen. Before and after semen wash, we cultured 15 ejaculates for aerobic and anaerobic bacteria, genital mycoplasma, and chlamydia. All semen samples had from one to five organisms isolated (total, 40 isolates) before the semen wash preparation. The mean number (+/- standard deviation) of isolates per sample was 2.67 +/- 1.35. After the semen were prepared, none of the samples showed a positive culture. The decrease in the number of samples with positive cultures and the decrease in the number of isolates is significant (P less than 0.0001). After sperm washing, electronmicroscopic studies did not show any microbes attached to any portion of the spermatozoa. We conclude that the method of sperm wash preparation used is effective in removing microbes present in human semen.