Early pregnancy tests work by binding the hCG hormone, from either blood or urine, to an antibody and an indicator. The antibody will only bind to hCG; other hormones will not give a positive test result. The usual indicator is a pigment molecule, present in a line across a home pregnancy urine test.
Gas and bloating is a sign that food is not being digested correctly by the body. An inadequate intake of water will cause excessive stomach bloating. Water benefits the body by aiding with digestion because it supports a majority of the body's daily functions.
Fortunately, stomach cancers are a very rare cause of gas and bloating; however, it does happen. This is caused by a tumor developing inside the stomach, causing problems such as bloating, gas, a feeling of fullness or discomfort. A hard stomach might also be one of the symptoms of stomach cancer.