The “behind-the-knee” test for menstrual tampon irritation

Miranda A. Farage, Kenneth W. Miller, William J. Ledger

Department of Obstetrics and Gynecology, The New York-Presbyterian Hospital, Weill Medical College, Cornell University, New York, USA.
Feminine Clinical Sciences, The Procter & Gamble Company, Cincinnati, USA.

DOI: 10.4236/ojog.2012.21006                

Abstract

Colposcopic inspection of the vagina is a routine component of the safety assessment of intravaginal products. However, colposcopic findings occur frequently in healthy women, raising questions about their relevance to intravaginal product safety. Practical disadvantages limit the utility of colposcopy for evaluating menstrual tampons, among them the presence of background microtrauma, the inability to assess effects during menstruation, and, importantly, the question of whether post-hoc assessments are sufficiently sensitive to detect small inflammatory changes. The Behind-the-knee (BTK) test is an alternative for evaluating inflammatory and tissue dryness effects of physical articles by their repeated application to the popliteal fossa under an elastic bandage. It enables concurrent parallel comparisons of experimental and control articles over time and substantially increases the sensitivity of detecting small changes in tissue inflammation. With this protocol, uncompressed experimental and control tampons yielded comparable relative and absolute erythema scores (after overnight recovery) as did colposcopic assessment of the lower genital tract 3 to 48 hours after menstrual use. Scoring erythema in the BTK test immediately after product removal increased the level of visually discernible inflammation 6-fold. In a study of commercial menstrual pads, subclinical inflammation visualized with cross-polarized light correlated with the frequency of subjective reports of discomfort during the test and discriminated the relative tolerability of the two products determined by market surveillance, providing added confidence in the predictive value of the test. We believe the BTK test to be a valuable alternative to colposcopy for assessing inflammation and dryness associated with menstrual tampons.

Keywords

Colposcopy; Behind-the-Knee; Menstrual Tampons

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	CONRAD/WHO (2011) Manual for standardization of colposcopy for the evaluation of vaginal products, update 2004. http://www.conrad.org/assets/attachments/Revised_Manual.PDF
[2]	Mauck, C.K., Baker, J.M., Birnkrant, D.B., Rowe, P.J. and Gabelnick, H.L. (2000) The use of colposcopy in assessing vaginal irritation in research. AIDS, 14, 2221-2227. doi:10.1097/00002030-200010200-00002
[3]	O’Neill, E., Reeves, M.F. and Creinin, M.D. (2008) Baseline colposcopic findings in women entering studies on female vaginal products. Contraception, 78, 162-166. doi:10.1016/j.contraception.2008.04.002
[4]	Fraser, I.S., Lahteenmaki, P., Elomaa, K., Lacarra, M., Mishell, D.R. Jr., Alvarez, F., et al. (1999) Variations in vaginal epithelial surface appearance determined by colposcopic inspection in healthy, sexually active women. Human Reproduction, 14, 1974-1978. doi:10.1093/humrep/14.8.1974
[5]	Norvell, M.K., Benrubi, G.I. and Thompson, R.J. (1984) Investigation of microtrauma after sexual intercourse. The Journal of Reproductive Medicine, 29, 269-271.
[6]	Ballagh, S.A., Mauck, C.K., Henry, D., Archer, D.F., Abercrombie, T., Callahan, M.M., et al. (2004) A comparison of techniques to assess cervicovaginal irritation and evaluation of the variability between two observers. Contraception, 70, 241-249. doi:10.1016/j.contraception.2004.03.002
[7]	Farage, M.A., Singh, M. and Ledger, W.J. (2009) Investigation of the sensitivity of a cross-polarized light visualization system to detect subclinical erythema and dryness in women with vulvovaginitis. American Journal of Obstetrics & Gynecology, 201, 20e1-20e6.
[8]	Wensveen, C., Kagie, M., Nagelkerke, N. and Trimbos, B. (2007) Interobserver agreement on interpreting hand drawings of colposcopy in women with borderline cytology to predict high-grade lesions. European Journal of Obstetrics, Gynecology, and Reproductive Biology, 135, 123-126. doi:10.1016/j.ejogrb.2006.08.001
[9]	Cummins, J.E. Jr. and Doncel, G.F. (2009) Biomarkers of cervicovaginal inflammation for the assessment of microbicide safety. Sexually Transmitted Diseases, 36, S84-S91. doi:10.1097/OLQ.0b013e3181994191
[10]	Farage, M.A., Gilpin, D.A., Enane, N.A. and Baldwin, S. (2001) Development of a new test for mechanical irritation: Behind the knee as a test site. Skin Research and Technology, 7, 193-203. doi:10.1034/j.1600-0846.2001.70309.x
[11]	Farage, M.A. (2009) Sensory effects and irritation: A strong relationship. In: Barel, A.O., Paye, M. and Maibach, H.I., Eds., Handbook of Cosmetic Science and Technology, Informa Health Care, New York, 381-289.
[12]	Farage, M.A., Miller, K.W. and Ledger, W.J. (2011) Can the BTK clinical test be used to evaluate the mechanical irritation potential for products intended for contact with mucous membranes? In: Surber, C., Elsner, P. and Farage, M.A., Eds., Topical Applications and the Mucosa, Karger, Basel, 125-132. doi:10.1159/000321063