A modified RT-PCR technique to screen for viral RNA in the semen of hepatitis C virus-positive men

BACKGROUND: Our objective was to use an adapted RT-PCR technique to assess the presence of hepatitis C virus (HCV) in semen and also in different density gradient semen fractions collected from men with chronic viral hepatitis participating in an assisted reproduction programme. METHODS: This study included 50 semen samples from 35 HCV+ men, with active viral replication assessed by RT-PCR, collected the day of oocyte retrieval and used for assisted reproduction. These samples were subjected to standard assisted reproduction sperm preparation conditions, using density-gradient centrifugation with 45 and 90% layers. Aliquots of semen, 45 and 90% fractions, and embryo culture media were frozen at -80degreesC for subsequent virological analyses. All aliquots were tested with a commercially available HCV RNA assay, adapted for use with semen after a number of technical changes. This assay yielded a sensitivity of 50-100 HCV RNA copies/ml and strongly diminished the effect of seminal amplification inhibitors. RESULTS: HCV RNA was detected in 7/50 (14%) semen samples tested, 5/35 (14.3%) men. HCV RNA was found in only 1/50 45% fractions but never in the 90% fraction or embryo culture media. Sera from 3/5 men contained 3.19-7.40x10(5) IU/ml, while the two others had 4.5 and 11.7x10(6) IU/ml. However, HCV RNA was quantified at <600 IU/ml in the HCV+ semen of these five patients. The ongoing pregnancy rate was of 20% (10/50) with one delivery at the time of the present report. No anti-HCV antibody was found in any of the women or the newborn. CONCLUSIONS: Although HCV is present at low concentrations in the semen of a few HCV+ patients, no purified sperm fraction (i.e. 90% fraction) used in assisted reproduction was HCV+ and no seroconversion was observed in the women and the newborn, thereby suggesting a very low risk of virus transmission. Nevertheless, because the presence of HCV in semen implies a possible risk of nosocomial contamination, safety regulations must be strictly applied in assisted reproduction laboratories.