Few things are as sad as seeing a negative result on a home pregnancy test when you’ve been trying so hard to become pregnant. Unfortunately, it does happen. When you see that result, you might wonder if you’re testing too early, if your test is broken, or if your test is expired, causing you to think, “Wait. Do pregnancy tests expire?” Many women never even consider the fact that pregnancy tests do come with expiration dates. Much like anything else on the market, there is a designated time frame in which pregnancy tests expire.

When Do Pregnancy Tests Expire?

The answer to this question varies. All pregnancy tests last approximately 2 to 3 years once produced. Typically, the less expensive pregnancy tests have a shorter shelf life, lasting two years once boxed and ready to place on store shelves. More expensive brand pregnancy tests don’t expire for three years. However, you must be careful not to assume that a test you bought a year ago will still work just fine. You never know how long a test was on a store shelf before you purchased it. That test you bought six months ago might already have been on the store’s shelf for two years, meaning it’s already expired.

Every brand of pregnancy test expires between 2 and 3 years after produced. Even some brands have different tests with different shelf lives. For example, a First Response digital test might have a different shelf life than a First Response test that isn’t a digital test.

Why Do Pregnancy Tests Expire?

Pregnancy tests expire because the chemical used to detect the level of hCG, the pregnancy hormone, in your urine is no longer effective. Once the chemical in the test is no longer effective, the chances of your test working properly are slim to none. Of course, that often leaves women wondering, “Do pregnancy tests expire on the exact date of expiration?”

To put it simply, the expiration dates on all pregnancy tests are written to include only the month and year of expiration. For example, if a test’s expiration date is 9/2013, then that test expires in September of 2013. Of course, that can be confusing for some women. Does this mean it expires on the first day of September or the last day of September? Typically, this means that as of October 1, 2013, this test is no longer good to use. However, some women prefer to be a bit more cautious and avoid using tests the first day of the month in which they expire.

Do Expired Pregnancy Tests Work?

Using the September expiration date as a further example, let’s discuss accuracy. Many women want to know if a pregnancy test simply knows to stop working on a specific date. For example, you might wonder, “Do pregnancy tests work one day after their expiration date?” While pregnancy tests manufacturers recommend discarding tests after the expiration date, taking a test that expires in September on the first day of October might still provide you with an accurate result. However, it’s best not to use that test.

The reason is that this test has been in a box on a shelf for a minimum of two to three years. At this point, the active ingredient designed to detect your hCG is no longer as strong and effective as it once was. So while your test might not have a magical power to say, “It’s 11:59 pm on September 30. It’s time to stop working correctly in one minute,” it’s best to simply discard expired pregnancy tests to eliminate the wonder and the doubt.

How to Choose the Right Pregnancy Test

Before you use the test you have under the bathroom sink, check the expiration date. Even if it expired only a week ago, toss it in the trash and purchase a new test. Additionally, be sure to read the expiration date on any test you purchase in the store. It’s better to know before you purchase the test than to find out once you return home and take the test the following morning.

Finally, make sure to check the expiration date on the interior packaging of each individual test. It’s rare, but some women have found that the box a test comes in has a different expiration date than the wrapper on the actual test inside the box. Use the closest expiration date as reference and discard if it has already passed.

Few things are as difficult to deal with as a negative pregnancy test. Do pregnancy tests expire? Of course they do. Don’t let something as silly as the test’s expiration date cause you unnecessary stress and doubt.

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