The cause of bad breath in women may be due to dental caries, tonsil stones, gastroesophageal reflux disease and other diseases. 1. Dental caries: Dental caries will lead to the formation of cavities in the teeth, food debris will accumulate in the cavities, leading to the proliferation of bacteria, bacterial metabolism will lead to bad breath. 2. Tonsil stones: Tonsil stones are formed by shedding epithelium and bacterial debris forming caseous material accumulated in the crypts, which will have a bad odor and lead to bad breath. 3. Gastroesophageal Reflux Disease (GERD): bile-containing duodenal contents abnormally reflux into the esophagus, or even the oral cavity, which can be malodorous and lead to bad breath. Women’s bad breath may also be seen in gastrointestinal power disorders, dental plaque, dental calculus and other diseases, if the symptoms of bad breath, persistent unrelieved, the need for timely medical treatment.