It is possible that bad breath may accompany H. pylori infection during the period. H. pylori belongs to the parasitic bacteria in the stomach, which is harmful to the human body, and after infection, it can lead to many lesions in the digestive system, such as duodenal ulcer, gastric ulcer, chronic gastritis, gastric cancer, etc. Since all of the above mentioned diseases can cause indigestion, and since the mouth is connected to the digestive tract, there will be a noticeable oral odor, which can be accompanied by halitosis. In addition, H. pylori produces ammonia through urease decomposition, which can also cause bad breath. In addition to bad breath, H. pylori infection is often accompanied by stomach pain, heartburn, and acid reflux. It is important to note that although H. pylori can be associated with bad breath, not all bad breath is necessarily due to H. pylori infection, and bad breath can also be associated with dental caries, poor oral hygiene, and consumption of more flavored foods. If you suspect the presence of H. pylori infection when you have obvious symptoms of bad breath, it is recommended that you consult a doctor as soon as possible for a detailed examination and treatment as prescribed by the doctor.