There are several types of mistakes people make when they take a home pregnancy test that can lead to inaccurate results. For example, not waiting to take a test until your period is late or drinking lots of water before the test. Potential test errors fall into two categories: those related to timing and those related to interpretation. Learn more about how to avoid a pregnancy test error.
What Not to Do Before Taking a Pregnancy Test
While unusual, drinking too much water before taking a test can produce a false negative result. This is because excess water can dilute the hCG levels in your urine so much that the test does not get a positive result. So, avoid drinking excessive amounts of water just before taking your test. Additionally, you can avoid this situation by using first-morning urine or being sure that you’ve held your urine for at least 4 hours.
Take the Test at the Right Time
Deciding when to take a home pregnancy test used to be simple: you waited until the day you missed your period and then you took a test. Today, you can get a pregnancy test that claims to tell you if you’re pregnant before you’ve missed your period. While these tests can produce an accurate result, it depends on the person. Not every person who is pregnant will have the same levels of hCG in their urine. This error isn’t inherent to the test, but rather, the timing of taking the test.
Read the Results at the Right Time
Most home pregnancy tests have explicit directions for taking the test and reading the results. The tests will usually give you the exact timeframe in which to look at the test to get your result.
Don’t Look Too Soon
You must wait until the end of the time allotted in the instructions to read the results of your test—which is usually one or two minutes. Use a stopwatch or a timer app on your phone to keep track.
Don’t Look Too Late
While you don’t want to read the results of your pregnancy test too early, you also don’t want to way too long. If you take a test when you wake up, then hop right in the shower, you might get on with your day without checking the test again. The instructions will usually give you the window in which the test results will be accurate—usually about five minutes. After this time has gone by, the test might produce a faint positive when in fact there was no hCG detected in your urine.
Confirm the Results
There are very few instances where a positive pregnancy test is wrong. A false positive pregnancy test is more likely to be caused by user error rather than a problem with the test. A negative result, on the other hand, may happen if you took a test too soon.
A Positive Result
If you are not pregnant, a false positive pregnancy test result is unlikely. The more likely explanation is that you had a chemical pregnancy (which produces enough hCG to turn a pregnancy test positive but miscarries shortly after) or a very early miscarriage.
A Negative Result
There are some situations where you would want to take another pregnancy test after getting a negative result. If the negative result was unexpected or you still do not have your period within a week of taking the test, you will want to retest. Sometimes, a negative test might not truly be a negative test—it might just be early for the test to turn positive. This is why most pregnancy tests recommend retesting after your body has had more time to produce detectable amounts of hCG in your urine.
A Word From Verywell
There are several reasons that home pregnancy tests can produce inaccurate results. The good news is, these errors can be avoided if you follow the instructions carefully. While most errors are related to user mistakes and not a problem with the test itself, purchasing a quality test makes it less likely it will have defects or be expired. If you get a test result that is unexpected, follow the recommendations provided by the test for retaking it (usually within a week). It’s also important that you contact your health care provider to confirm the result you get with a home pregnancy test.
