The incidence of T. vaginalis infection has been increasing around the world over the past decade.

This has lead to insight of the importance of this microorganism as a serious problem in reproductive health outcomes including pelvic inflammatory disease, pregnancy complications and an increased risk of HIV acquisition.

For natural fertility, not only optimal semen sample that contains a normal and motile sperm cell number is needed but also to be free of any microorganism including T. vaginalis.

Here, we present a case report of a male patient with unexplained infertility who underwent an IVF cycle. The ejaculated sample from this patient was collected for IVF purposes and immediately analyzed under microscopic examination. Contamination with T. vaginalis and several polymorphonuclear cells were shown in the semen sample. In addition, severe asthenozoospermia was observed which has a negative impact on achieving oocyte fertilization.

A laboratory protocol using density gradients separation and a special device, the ProInsert from Nidacon, was performed as a preparation method of the semen sample for capacitation and recovery of motile sperm cells needed for the IVF procedure.

We found that the density gradients with the ProInsert effectively removed T. vaginalis microorganisms and polymorphonuclear cells, leaving only the motile sperm and giving rise to a successful in vitro oocyte fertilization and embryo development.

Embryos were transferred but unfortunately, pregnancy was not achieved due to an embryo implantation failure that may be caused by endometrial T.vaginalis infection from asymptomatic female partner.