Disposable period underwear varies widely in performance, with prices up to twice as high across brands

A new study has found that disposable period underwear products vary significantly in absorbency performance, with prices differing by as much as twofold across brands.

The Korea Consumer Agency on Tuesday released the results of a comparative assessment of seven disposable period underwear products, evaluating absorbency performance, wearability based on real consumer use, basic quality, safety and per-unit price. The products tested were from Natural Cotton, Liberty, Soonsuhanmyeon, Sofy, Tempo, Rael and Goodfeel.

Liberty was the least expensive at 580 won per unit, while Sofy was the most expensive at 1,160 won. All seven products met applicable standards for basic quality and safety, and no volatile organic compounds were detected. The Goodfeel product recorded the lowest rewet level — the degree to which absorbed menstrual fluid seeps back onto the skin.

In tests measuring how quickly each product fully absorbed menstrual fluid, four products — Natural Cotton, Liberty, Soonsuhanmyeon and Sofy — absorbed a 3-milliliter volume in about two seconds. At 5 milliliters, Natural Cotton was relatively fast at 3.6 seconds, while Rael took more than 20 seconds, the slowest among the products tested.

In a wearability assessment by 110 female consumers in their 20s to 40s who wore the products themselves, Liberty and Rael received relatively favorable ratings for fit. Measurements of internal humidity found that Natural Cotton, Soonsuhanmyeon, Sofy and Rael had comparatively lower moisture levels inside the product.

A review of product packaging and online listings found that Natural Cotton, Rael and Liberty had used claims such as "non-toxic" without objective supporting evidence. The Korea Consumer Agency requested corrections, and all such claims have since been removed.

The Korea Consumer Agency advised consumers that, since disposable period underwear products differ in fit, sizing and absorbency, they should compare body type, recommended size, absorbency performance and price before making a purchase.