TESTING THE MUTAGENIC POTENTIAL OF POLYVINYLPYRROLIDONE AND METHYL CELLULOSE BY SISTER-CHROMATID EXCHANGE ANALYSIS PRIOR TO USE IN INTRACYTOPLASMIC SPERM INJECTION PROCEDURES

The treatment of infertility due to severe oligoasthenoteratozoospermia has been revolutionized by the introduction of the technique of intracytoplasmic sperm injection. However, techniques which involve injection into the oocyte of polyvinylpyrrolidone solution as a vehicle for the selected spermatozoon have caused concern since the possible harmful effects of polyvinylpyrrolidone have not been fully investigated. This study was performed to investigate the potential mutagenic effect of polyvinylpyrrolidone on cultured human somatic cells, at the concentration used for intracytoplasmic sperm injection, in addition to a possible alternative vehicle, methyl cellulose, using the technique of sister chromatid exchange analysis. The results showed no increase in the basal frequency of sister chromatid exchanges with polyvinylpyrrolidone (median 5.0, 95% interval 5.00-6.00) or with methyl cellulose (median 6.0, 95% interval 4.22-6.00) in comparison with the negative control (saline: median 6.0, 95% interval 5.00-7.00), and in contrast to the positive control (mitomycin C: median 25.0, 95% interval 22.23-28.77). This finding suggests that polyvinylpyrrolidone and methyl cellulose do not cause DNA lesions resulting in sister chromatid exchanges, and provides reassuring evidence concerning their use in sperm injection procedures.