By the 1990s, the design had made its way to most of the Western World, and thong underwear became popular. As of 2003, thong underwear is one of the fastest selling styles among women and is even gaining some popularity among men. One advantage attributed to the wearing of thong underwear is that no "visible panty line" can be seen even under a thin, light-colored, or skin-tight garment. The main drawback to thong underwear is that the fabric must be pulled directly between one's buttocks, which many people find unattractive and/or uncomfortable. If worn for long periods of time, they can also lead to urinary tract infections in women due to anal bacteria contamination.