Taking a pregnancy test is usually the first thing you do when you think you might be pregnant. While many tests claim a high accuracy percentage, it is still possible to get either a false positive or false negative result.
How a Home Pregnancy Test Works
When you get pregnant, a hormone called human Chorionic Gonadotropin (hCG) is produced. This pregnancy hormone, which is more commonly referred to as hCG, enters your bloodstream and urine. The hCG concentration levels continue to increase as the pregnancy progresses.
Typical pregnancy tests work by holding the stick in your urine stream or dipping it into a container of your urine. If it detects a minimum concentration level of hCG, a positive result will occur. Any hCG concentration less than that level will show a negative result.
Different home pregnancy tests are more sensitive than others and are able to detect lower concentration levels of hCG. This is why some brands can claim to detect a pregnancy earlier than other brands. Read our blog post “Which Home Pregnancy Tests Are Most Accurate” to find out more.
How a False Positive Occurs
It is not common, but a home pregnancy test can show a positive result when you are not really pregnant. This is known as a false positive. The following are a few reasons why you may get a false positive:
- Interference from medications: Certain medications, like Methadone, Promethazine, and Chloradiazepoxide can affect the results. Fertility drugs containing hCG can also lead to a false positive.
- A very early miscarriage occurred: After a pregnancy loss happens, there can still be detectable levels of hCG in your body at the time of a test.
How a False Negative Occurs
A false negative means that the test showed a negative result, but you are actually pregnant. A false negative is much more common than a false positive and can happen for a variety of reasons, including the following:
- You took the test too soon. The hCG concentration levels may not have been high enough for the test to detect. Waiting to take the test one week after you miss your period can help prevent this type of false negative.
- There was not enough urine or the urine was diluted. This may have prevented the test from accurately detecting the hCG. To get the best results, use a home pregnancy test first thing in the morning to ensure that your urine is the most concentrated.
Additionally, a false positive or a false negative can occur because the test malfunctioned or because of user error. That is why it is so important to follow the instructions exactly to get the most accurate results.
Avail NYC exists to be a safe haven for women and men facing an unexpected pregnancy or seeking support after an abortion. We are not a medical provider.