Trusted Information for Healthy Pregnancies
Pregnancy Test
A False Positive Pregnancy Test – Why Does It Happen?
Feb 8th
To understand why you may sometimes end up with a false positive pregnancy test you need to understand how the common or garden variety of home pregnancy test kits work.
The modern pregnancy test has made it a simple matter to confirm a pregnancy by the simple expedient of peeing on a stick.
The test device works by detecting the presence of HCG or human chorionic gonadotropin in the blood or urine of a pregnant woman. The lateral low technology is used for this and if the test is positive, the urine usually changes color and a colored line shows up in the testing strip area.
The home pregnancy testing kit is very reliable and one study showed that when used by experienced technicians, it had an accuracy level of over 97%, the same professional laboratory testing in terms of accuracy.
In the hand of consumer, however, the accuracy of the test was shown to be about 75% only. This goes to show that they may be a high level of users who do not use the testing device properly or as instructed.
This gives rise to a false positive pregnancy test and equally as well work the other way around; by throwing up a false negative. Improper use and failure to follow instructions is a big reason why a false positive pregnancy test may show up.
Sometimes a particular constituent of one’s urine can give rise to an evaporation line which could be mistaken for a positive result in a test kit. In this case, testing should be done again in a few days to get the correct result.
In rare cases, the testing kit itself may have some anomaly or manufacturing defect or sometimes the expiry date may have passed. So be sure to check the date of manufacture on the package and also the date of expiration because an expired product may not give you correct results.
Certain medications may increase levels of the HCG hormone in the body and may therefore result in a false positive pregnancy test.
Understand that a false positive pregnancy may result from a number of different factors as stated above and also other possible reasons. So it is important to follow instructions fully and correctly.
Make sure that the brand you buy is good quality and well within the date of expiry. Also do not depend on the home test entirely, have the findings confirmed by a doctor’s test for an accurate result.
When Does The Pregnancy Test Show A False Positive?
Dec 18th
The common home pregnancy test kit is usually quite fool proof and 99% of the time it will give you a correct reading of the pregnant or non pregnant state of a woman.
However, in some rare cases, a home pregnancy test will display a false positive and there could be several reasons for this:
- Not following directions properly can sometimes result in a false positive result.
- The home test kit is either contaminated or is faulty. On rare occasions there could be something wrong with the strip that you may be using and therefore may show a false positive
- Contamination or impurity of the urine sample. A home test kit usually requires a woman to use a urine sample for taking the test. If the sample is collected in a cup having traces of detergent or if there is some blood in the sample, this could result in a false positive.
- Certain prescription medications can interfere with an accurate result so that if one is on any kind of tranquilizers, diuretics, anticonvulsants etc, there are chances of the test showing a false positive
- Certain medical conditions can cause the test result to show a false positive, particularly if there is a disorder or tumor of some sort in the reproductive tract.