Interference potential of personal lubricants and vaginal medications on ThinPrep® pap tests

Background: the effects of water-based speculum lubricants on both conventional papanicolaou smears and liquid-based papanicolaou tests have been well documented. however,studies are lacking concerning the effects on these tests of personal lubricants and/or vaginal medications. lubricants containing carbomers or carbopol polymers are known to interfere with thinprep® papanicolaou test processing. many over-the-counter products that advertise effects lasting several days may contain these substances. this study tests 2 popular personal lubricants (ky warming liquid [johnson & johnson,new brunswick,nj] and replens [kora health care,swords,ireland]) and one yeast medication (monistat 7,mcneill-ppc,inc.,skillman,nj) for interference on thinprep® papanicolaou tests. methods: the residual specimens from 270 thinprep® vials were combined to form 100 homogenous thinprep® papanicolaou specimens. nine groups of 10 vials were then contaminated with 20 μl,100 μl,and 500 μl of each of the 3 products. one group of 10 vials served as control. cell counts were performed after processing the specimens onto slides,and the results were recorded. results: ky warming liquid had no effect at any volume of contamination. replens caused a drastic reduction in cellularity at even the lowest volume. monistat 7 reduced cellularity incrementally as the volume increased. conclusion: the potential exists for some over-the-counter lubricants and vaginal medications to interfere with the thinprep® papanicolaou test.