Period underwear is a reusable garment designed to absorb menstrual flow, functioning as a complete replacement or a reliable backup for traditional disposable products like pads and tampons. These garments have gained significant traction as a comfortable and sustainable alternative to conventional menstrual hygiene options. To determine if period underwear is a good choice, it is helpful to evaluate its performance, maintenance requirements, safety profile, and long-term value.
Functional Performance and Capacity
Period underwear works through a multi-layered system built into the gusset. The layer closest to the skin is designed to be moisture-wicking, quickly pulling fluid away to keep the wearer feeling dry and preventing skin irritation. Directly beneath this is an absorbent core, often made from specialized microfibers, which traps and locks away the menstrual fluid.
This core is protected by a leak-proof barrier, commonly made from a breathable but waterproof material like Polyurethane Laminate (PUL), which prevents the fluid from soaking through to clothing. Capacity varies by brand and style; light-absorbency pairs hold the equivalent of one to three tampons. Heavier styles absorb the fluid equivalent of four to seven tampons, making them suitable for moderate or heavy flow days or overnight protection. Performance relies on selecting the correct absorbency level and ensuring a proper fit to maintain the leak-proof seal.
Practicality, Cleaning, and Longevity
The maintenance routine for period underwear is a consideration for users switching from disposable products. After use, the underwear must first be rinsed under cold water until the water runs clear. Using cold water is important because hot water can cause the blood proteins to set into the fabric, making stains harder to remove.
Once rinsed, the garments can be machine washed with a mild detergent on a cold or delicate cycle. Users should avoid using fabric softeners or bleach, as these chemicals can coat the absorbent fibers and reduce the garment’s capacity and effectiveness over time. To maintain the integrity of the leak-proof layer, period underwear should always be air-dried rather than placed in a high-heat tumble dryer. With proper care, a pair is designed to last for two to five years or through a minimum of 60 wash cycles.
Health and Material Safety
The materials used in period underwear are important for both performance and health, with most garments featuring layers of cotton, bamboo, or synthetic blends. A concern revolves around the use of Per- and polyfluoroalkyl substances (PFAS), which have historically been used in textiles for stain and water resistance. Because the vulva is an absorbent area, the presence of these chemicals is a health concern, leading many brands to certify their products as PFAS-free.
Silver or nanosilver is sometimes used as an antimicrobial treatment intended to control odor. However, experts have raised concerns that these particles could disrupt the natural balance of the vaginal microbiome by killing beneficial bacteria. Consumers can look for third-party certifications, such as OEKO-TEX Standard 100, which ensure that the textiles have been tested for harmful substances.
Environmental and Cost Benefits
The positive environmental impact is a strong argument for period underwear compared to disposable options. A person who menstruates may use over 11,000 disposable menstrual products in their lifetime, most of which contain plastic components that take hundreds of years to decompose in landfills. By choosing reusable garments, users can reduce their contribution to waste and lower their carbon footprint.
Period underwear is also economically favorable over the long term, despite the higher initial investment. A small collection of reusable garments can replace the need for disposable products for several years. This shift from a recurring monthly purchase to a one-time investment results in considerable cost savings over time.