Evaluating Skin Sensitivity of the Vulva

Studies of skin sensitivity utilizing irritants may be conducted on exposed or partially occluded skin. The characteristics of the vulva differ greatly when compared to exposed skin. In contrast to exposed skin, the vulva is considered occluded tissue, and it also has increased hydration,11 more hair follicles, sweat glands and increased blood flow.10

The current authors recently found that individuals with vulvar erythema at study enrollment also reported significantly more facial erythema resulting from a topical product.24 In many cases, sensitivity in the vulvar region may result from overuse of topical hygienic and medicinal preparations.25 Safety testing of feminine hygiene products considers the potentially higher permeability of vulvar skin and increased secondary sensitization.10

The best method of evaluating vulvar sensitivity to irritation utilizes the combined methods of assessing blood flow, pH and color reflectance.16