Just like any other substances or chemicals, this active ingredient has its own shelf life. Pregnancy tests are typically effective within one to three years after they were manufactured.
Take note that the maximum shelf life is counted starting from the date that the kit was manufactured and not based on when you got it from the drug store. Even if you bought your pregnancy test stick a few months ago, it may be stocked in the pharmacy for years. Expiration dates may also vary per manufacturer so it is best to refer to the individual labels for this information. Knowing how pregnancy tests work, it is highly likely that expired pregnancy test accuracy will be significantly lower when compared to the results that it can provide if used within the recommended time frame.
Using an expired pregnancy test also means that the active ingredient found inside will have less ability to react to the hCG in your urine. This can lead to a false negative result, meaning, you are pregnant but the test revealed negative since it has no ability to detect the pregnancy hormone in your urine anymore.
Can an expired pregnancy test give a false positive? Yes, it is also possible, especially when you stored it in a hot and humid area like your bathroom. False results are typically expected on expired pregnancy tests, so it is better to avoid using them if you want to avoid getting false hopes.
Generally, it is not recommended to use an expired pregnancy test. A blood test can detect hCG about nine days after conception, and a urine test can detect it 12 to 14 days after conception, according to the Cleveland Clinic , although it varies—some especially sensitive urine tests can detect a pregnancy even earlier. Then it remains consistent and starts to go down after delivery. Back to top. An at-home pregnancy test is designed to find hCG in pee 2.
If the hormone is present, it triggers a chemical reaction and the test signals that you're pregnant. If hCG is not present, the test will say you aren't pregnant. Some tests use plus and minus signs. Some digital pregnancy tests have a screen that plainly reads "pregnant" or "not pregnant. Seems simple, right? As Ina Garten would say, "How easy is that? Ultrasounds typically can't detect a pregnancy until a little later in your pregnancy and that's why at-home tests are so useful.
If you take a standard pregnancy test with line indicators, it's important to check the results according to the specific instruction of the test. If you let it sit too long before reading the results, urine on the test can evaporate and make it look like you have two lines instead of just one.
That might cause the test to look like it has a faint second line—making it positive—but it really only has one. The best way to avoid this: Read the pregnancy test's directions and follow them exactly. The popular pregnancy test brand First Response, for example, instructs users to wait three minutes after taking the test, then read it as soon as possible 4.
The second most common reason Dr. Abdur-Rahman's patients get false positives is because the test is expired, he says. Abdur-Rahman says. If you take a pregnancy test too soon after taking a fertility drug that contains hCG—like some injections that are often part of in vitro fertilization—you could get a false positive.
Most miscarriages occur in the first 13 weeks of pregnancy 5. After you give birth or miscarry, hCG can persist in your body for months, Dr. Williams says. One study published in The Journal of Clinical Endocrinology and Metabolism estimates that it takes four to six weeks for hCG levels to return to normal after a person has a miscarriage 6.
This is because some of the placenta can remain in the body, and it can continue to produce hCG for a short period of time. An ectopic pregnancy happens when a fertilized egg ends up growing outside the uterus—usually in a fallopian tube—instead of inside the uterus 7. The date is stamped right on the packaging, so check it before you buy the test. What to Expect follows strict reporting guidelines and uses only credible sources, such as peer-reviewed studies, academic research institutions and highly respected health organizations.
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Do Pregnancy Tests Expire? When to Take a Pregnancy Test. Medically Reviewed by Mark Payson, M. Medical Review Policy All What to Expect content that addresses health or safety is medically reviewed by a team of vetted health professionals. Here's what to know about the right time to take a pregnancy test and whether or not they expire.
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