Bitter mouth and nausea cannot determine whether you are pregnant. If you have a recent history of sexual intercourse and your period is delayed for more than a week, you can determine whether you are pregnant through an early pregnancy test. Most of the symptoms of bitter mouth and nausea are caused by bile reflux due to poor gallbladder function and poor gastrointestinal motility, which are mostly seen in patients with cholecystitis, gallstones, bile reflux gastritis and reflux esophagitis. Usually pay attention to regular meals, eat less and more meals, eat more light and easily digestible food, drink more water, eat more fresh vegetables and fruits, and avoid greasy, cold, spicy and stimulating food.