Why do women get yellow stains in their underware?

Yellow stains in women's underwear are often caused by a combination of factors, including menstrual fluid, sweat, and the breakdown of bodily oils. Additionally, certain hygiene products, such as soaps or detergents, can react with bodily fluids and contribute to discoloration. Over time, these substances can accumulate and result in noticeable staining. Regular washing and proper hygiene practices can help minimize these stains.