[Bacteriological analysis of semen samples from sperm donors]

Area of Science:

• Microbiology
• Andrology
• Reproductive Medicine

Background:

• Semen bacterial culture lacks established reference values for contamination and infection.
• Existing criteria for male urinary tract infections were adapted to assess semen bacterial load.

Purpose of the Study:

• To investigate the prevalence and types of bacteria present in semen samples from sperm donors.
• To establish a threshold for unqualified semen culture based on bacterial colony counts.

Main Methods:

• Bacterial culture was performed on 3,160 semen samples from sperm donors.
• An automatic colony counter and microbial identification instrument were utilized.
• A threshold of ≥104 colony-forming units/ml was set for unqualified semen culture.

Main Results:

• 85.57% of semen samples showed bacterial growth.
• Gram-positive bacteria constituted 87.89% of identified bacteria.
• The predominant species included Staphylococcus epidermidis, Hemolytic staphylococcus, and Corynebacterium.

Conclusions:

• Sperm donors exhibit a high rate of carrying bacteria in their semen.
• A diverse range of bacterial strains were identified, predominantly Gram-positive.
• These findings underscore the importance of monitoring bacterial presence in donor semen.