Influence of bacteria and leukocytes on the outcome of in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI)

Abstract

Summary. The influence of bacteria and/or leukocytes on the outcome of IVF or ICSI is influenced by three factors which have little in common with in vivo conditions: 1) The process of ejaculate preparation (swim‐up, Percoll) with antibiotic buffered media; 2) The small amount of inseminated spermatozoa (100000 per culture); 3) The short cultivation time. From the very beginning, these factors limit whatever the influence of bacteria and leukocytes on fertilization and embryonic development in vivo may be. Despite the contradictory results published so far, the influence of bacteria and/or leukocytes on the functional integrity of spermatozoa during the process of IVF or ICSI can be ignored. Furthermore, during IVF or ICSI the spermatozoon does not act as a vector for the transportation of bacteria into the ooplasm.