False negative results are more common than false positives - and are primarily due to inaccuracies in timing of the test or carelessness in the test procedure itself. Please follow test instructions with circumspection and precision. A false negative result can also stem from using a diluted urine sample and/or from taking a test too early in pregnancy. First morning urine contains the most concentrated presence of hCG - which makes it the ideal sample for pregnancy testing.

It is possible to get a false positive test result. This happens when a doctor or laboratory has not performed a confirmatory antibody test before giving people their results. When a person has an antibody test, the lab usually runs two different kinds of tests. One is called an EIA test which is highly sensitive. It can sometimes overreact, so a positive result with the EIA is usually followed up with a RIBA test which is a sophisticated, highly-specific, antibody test.

Yes! Not every woman will test positive by HPTs even though they are late for a period. If you think you are pregnant, call your health care provider and ask for a quantitative hCG to be sure. The information on this site is intended for informational purposes only and is not a substitute for the advice of a qualified healthcare professional. If you have any concerns about your health, please consult a qualified health care provider immediately.

The Pap test is a screening test and, like any such test, it is not 100-percent accurate. Although false positive and false negative results do not occur very often, they can cause anxiety and can affect a woman's health. A false positive Pap test means that a patient is told she has abnormal cells, but the cells are actually normal. A false negative Pap test occurs when a specimen is called normal, but the woman has a significant abnormality that was missed.

Yes. Most women will register on HPTs by the time they are a few days late for a period, but not everyone will. If you suspect you are pregnant, you should see your doctor for a quantitative hCG test no matter what result you get from an HPT. Note: This is a new test with a purple cap (the old version that detects 20 mIU is all white). There are still a number of false positives being detected, and if you receive one the company would like you to call with the lot number on the box.

In 2-5% of individuals who have recently received an influenza vaccination, there may be a temporary false positive EIA.

Yes, a false positive test means the test looks as if it is positive, but it is really negative. This happens more often in people who have a low risk for the disease. It is important to confirm the test result a second time.

Yes, this happens when the person tested may have an early infection. He or she may not have developed antibody levels high enough that the test can measure. In addition, some people may lack the immune response necessary for the test to work well.

No. Clomid will not cause a false positive result on a hpt. The only infertility therapy that will cause a false positive is hCG. HCG is the hormone that all HPTs measure. If you are taking only clomid to assist you in Oing, and you get a positive result on a HPT, congratulations! you are pregnant.

No. Home pregnancy tests only check hCG levels, not progesterone. They are completely different hormones.

Yes. Such results can be caused by technical problems with the biopsy equipment; not getting the correct sample; the method of biopsy done was not suitable for the lesion(s) present.

It is important to bear in mind that common diseases, such as atrial fibrillation and stroke, occur as a result of the interplay of both environmental (including lifestyle and other health and medical conditions) and inherited risk factors. As a result, having a specific genetic risk factor for a common disease does not mean that one will necessarily develop the disease; and not having a certain risk variant does not eliminate the possibility of developing the disease.

individual with two copies of the risk variants will receive a positive result for deCODE MI™, and those with only one or no copy of the risk variants will receive a negative result for the test. Back to top of page