Effect of Hyaluronic Acid (HA) as a Substitute for Polyvinyl-Pyrrolidone (PVP) on ICSI Outcome

Abstract

Objectives: Synthetic macromolecule polyvinylpyrrolidone (PVP) is routinely used in conventional ICSI procedure. However, it has been reported that PVP induces detrimental effect on embryo development including chromosomal abnormality. It suggests that the avoidance of PVP in ICSI procedure should be a reasonable choice. HA, a kind of Glycosaminoglycans (GAGs), is found at high concentration in the fluid of the female reproductive tract of several mammalian species. The aim of this investigation was to examine whether HA could be used as a substitute for PVP in ICSI procedure. Design: ICSI was performed in PBS supplemented with either PVP or HA. After ICSI, fertilization and development were evaluated in two treatments. Materials and methods: After oocyte retrial, oocytes were enzymatically denuded. MII oocytes derived from one patient were randomly divided into group A (n=28) and group B (n=22) and ICSI were performed with husband spermatozoa which immobilized in either 5% PVP or 2.5 mg/ml HA, respectively. At 18 hours after microinjection, 2PNs were co-cultured with cumulus cells in YS medium containing 10% hFF until day 3 or day 5. Quality of embryos was evaluated on day 3 into four grades (good, medium+, medium and poor) based on their fragmentation and morphology. The blastocyst rates were also evaluated in two groups. Result: Viscosity of HA allowed for reduction of sperm motility and control of sperm movement inside injection pipette like PVP. Fertilization rates were not different between group A (78.6%) and group B (81.8%). On day 3, however, the rate of good quality embryos of group B (61.1%) was higher than those of group A (45.0%). The blastocyst rate of group B (77.8%) was also higher than that of group A (59.0%). Conclusion: This result suggests that HA should be a good candidate for reducing the potentially harmful effects derived from PVP in ICSI.