hygiene products that are meant to cleanse may lead to allergic reaction and irritation, as the vagina naturally flushes out bacteria. Many health professionals advise against douching because it can change the balance of vaginal flora and acidity. Risks The different products may carry some health risks, some of which might be proven, others speculative. Toxic shock syndrome: A rare illness that may occur when tampons are worn for long periods of time, although not directly linked to tampon use but caused by poison linked to bacteria of the Streptococcus pyogenes or Staphylococcus aureus type. Irritation: Can be caused by fragrances, neomycin (adhesive on pads), tea tree oil, benzocaine. Inflammation can also be a risk associated with some products. Yeast infection: A fungus. Bacterial vaginosis: Overgrowth of naturally occurring bacteria in the vagina that leads to a type of vaginal inflammation. The imbalance of bacteria from its natural state has been connected to bacterial vaginosis Exposure to chemicals: some period underwear companies (like Thinx, Ruby Love, and Knix) are facing class action lawsuits for products containing harmful toxins like per- and polyfluoroalkyl substances (PFAS) which may be linked to adverse health outcomes like cancer. Society and culture According to the World Health Organization, as of 2018 there are about 1.9 billion women who are of reproductive age. In low-income countries, women's choices of menstrual hygiene materials are often limited by the costs, availability and social norms. Not only are women's choices limited but, according to the WHO and Unicef, 780 million people do not have access to improved water sources and about 2.5 billion people lack access to improved sanitation. The lack of proper hygiene leads to a harder time for women to manage feminine hygiene. Costs and tax Tampon tax is a shorthand for sales tax charged on tampons, pads, and menstrual cups. The cost of these commercial products for menstrual management is considered to be unacceptably high for many low-income women. At least half a million women across the world do not have enough money to adequately afford these products. This can result in missing school or even dropping out. In some jurisdictions similar necessities like medical devices and toilet paper are not taxed. Several initiatives worldwide advocate to eliminate the tax all together. In some countries, such petitions have already been successful (for example parts of the UK and the United States). Access to products in prisons