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Updated: May 30, 2026

Sperm Collection of Differential Quality Using Density Gradient Centrifugation
Published on: November 29, 2018
Herpes virus infected spermatozoa following density gradient centrifugation for IVF purposes
V Michou1, S Liarmakopoulou, D Thomas
1Locus-Medicus SA, Ampelokipi, Athens, Greece. locus@otenet.gr
Abstract:
Studies have documented the presence of herpes viruses in semen. The aim of our study was to determine whether they persist in semen samples following two-density gradient centrifugation for IVF purposes. Semen samples were collected from 109 men seeking fertility evaluation, prior to IVF treatment. Routine semen analysis was performed according to WHO guidelines. Each sample was treated in a two-density gradient centrifugation using PureSperm (PS). Both untreated and treated samples were screened for the presence of herpes viruses, using PCR. Kruskal-Wallis, chi-square and binomial statistical tests were used; P ≤ 0.05 was considered statistically significant. No statistically significant associations were observed between semen parameters and viral presence. Viral DNA was detected in 54% of semen samples: HSV1/2 in 32 samples, EBV in 49, CMV in 47, HHV6 in 9, HHV7 in 4 and VZV in none. PS gradient failed to remove CMV in 89.36%, HSV1/2 in 59.38% and EBV in 22.45% of samples, while HHV6 and 7 were completely removed. Especially HSV1/2 and CMV seem to persist even following PS treatment. These observations indicate the possible risk of oocyte becoming infected during insemination, by IVF or intracytoplasmic sperm injection, with unknown sequelae. Further studies are required to determine whether any correlation exists between their presence, implantation rate and the outcome of pregnancy.
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