Papanicolaou tests

Clinical question

Does using a small amount of water-soluble lubricant on the speculum reduce the adequacy of Pap tests?

Evidence

Four RCTs address this question. Conventional cervical cytology smears (glass slides) were used in all studies.1–4

• The largest RCT1 examined 2906 patients.

  • -Water-soluble lubricant was compared with tap water.

  • -No difference in the quality of cytology was found.

• Two smaller RCTs (N = 182 and N = 70)2,3 and a quasi-randomized (randomized by month) trial4 of 3460 Pap tests found no difference in test adequacy.

Context

• One study found that “more than the usual amount of gel” (ie, a 1- to 1.5-cm “ribbon” of lubricant directly on the cervical os) could affect Pap test adequacy.5

  • -Clinicians do not do this; it is not applicable to regular clinical practice.

• No RCT has assessed lubricant influence on liquid-based Pap test results.

  • -A retrospective review of 4068 liquid-based Pap tests found 15 (0.4%) had obscuring material causing misinterpretation of results: approximately half might have been related to lubricant use (combined with technologist inexperience).6

  • -Two studies applied lubricant directly into liquid-based cervical cytology samples.7,8

    • —One reported reduced cell counts (after this purposeful dilution), but the effect on adequacy was not assessed.7 Of note, Aquagel reduced cell counts more than K-Y jelly did.7

    • —The second demonstrated no effect on liquid-based Pap test outcomes.8

• One RCT also examined if lubricant affected testing for chlamydia and found no effect after 5535 samples.4 (Gonorrhea was considered too uncommon to assess.)

  • -A laboratory study demonstrated that gel mixed with chlamydia and gonorrhea cultures did not affect plating or diagnosis.9

Bottom line

A small amount of water-soluble lubricant on the speculum does not reduce the quality of Pap tests and probably does not affect microbiologic results. Current evidence suggests the adequacy of liquid-based Pap tests would be minimally or not at all affected.

Implementation

Pap tests remain an essential aspect of cervical cancer screening. Recommended screening intervals have been extended for many patients,10 but some physicians continue to advise intervals shorter than those suggested by newer guidelines.11 Some patients, particularly smokers, the obese, and those with depression, might be at risk of being screened too infrequently.12 Reminder letters increase the proportion of patients with adequate screening.13 In general, patients are accepting of reminders,14 and providers appreciate the utility of recall systems for Pap smears.15 Practices should consider developing registries for recall and reminder systems, focusing on those patients who are less likely to be screened. Clinicians can use water-soluble lubricant on speculums as needed.