The last day of my period was the 20th of November. I have not had any symptoms of pregnancy but I think that I may be pregnant. I should have already had or started my period by now but I am still waiting. I would be around 3 weeks pregnant but I am not sure if it is to early to take a pregnancy test.
Learn more about this top honor. The fecal occult blood test (FOBT) is a lab test used to check stool samples for hidden (occult) blood. Occult blood in the stool may indicate colon cancer or polyps in the colon or rectum â though not all cancers or polyps bleed. Typically, occult blood is passed in such small amounts that it can be detected only through the chemicals used in a fecal occult blood test.
Occult gastrointestinal bleeding usually is discovered when fecal occult blood test results are positive or iron deficiency anemia is detected. Fecal occult blood testing methods vary, but all have limited sensitivity and specificity.t is normal to lose 0.5 to 1.5 mL of blood daily in the gastrointestinal tract, 3 and melena usually is identified when more than 150 mL of blood are lost in the upper gastrointestinal tract. 3 FOBTs have sufficient sensitivity to detect bleeding that is not visible in the stool.