Blog- How to get pregnant?
Do pregnancy tests expire?
An ad for tampons pops up on your social media feed. You glance at the calendar, realize you’re feeling more tired than usual, and wonder: “Wait — when was my last period?”
These moments always seem to happen at the most inconvenient times. The drugstore is closed , so you rummage through your bathroom drawer and find an old pregnancy test. But a nagging doubt creeps in: Is it still good? Do pregnancy tests expire?
The short answer is yes, pregnancy tests do expire. Here’s why...
Why do pregnancy tests expire?
First, a quick lesson on how home pregnancy tests work.
Home pregnancy tests detect levels of the pregnancy hormone hCG (human chorionic gonadotropin) in your urine. Your body produces hCG once a fertilized egg implants in your uterine wall.
Pregnancy tests work by using antibodies attached to colored labels to bind hCG, which results in a color change at the test line. This traditionally occurs with the appearance of marker lines, or in the case of the Clearblue® Early Digital Pregnancy Test, the line is read by an optical sensor, which then displays the result as the words “Pregnant” or “Not Pregnant” on an LCD screen.1,2
The antibodies and other components used in home pregnancy tests to detect hCG don’t last forever — hence the expiration date. Once a test has hit its expiration date (typically one to three years after it was manufactured), the antibodies aren’t as good at detecting hCG. And that can cause problems, particularly in the form of false negatives.
How long are pregnancy tests good for?
Pregnancy test expiration dates vary by manufacturer. Clearblue® pregnancy tests have expiration dates printed in two places on the packaging:
- The bottom of the box
- The foil wrapper of each test stick
This means it’s totally fine if you take tests out of the box — but you should never unwrap a test until you’re ready to use it. Clearblue® pregnancy tests should be stored in their foil wrappers until they’re ready to be used immediately.
The expiration date is based on when the test was manufactured. It’s important to check the expiration date when you buy your test; the expiration date may be sooner than you expect. Make sure to check the expiration date every time you test as well. A two-pack of tests you purchased more than a year ago could have unexpectedly expired.
Do digital pregnancy tests expire?
Yes. Since digital pregnancy tests work the same way that all home pregnancy tests work — by detecting
hCG hormone levels in your urine — the antibodies and other components in the test can lose efficacy.
Do expired pregnancy tests work?
No. Expired pregnancy tests cannot be counted on to produce a reliable result. One sign that a
pregnancy test may be expired is an increased likelihood of a false negative result. This can occur
because some components might degrade and fail to detect the presence of hCG, a hormone that a non-expired test would typically identify. A false negative can delay decision making, lifestyle changes and prenatal care.
Can expired pregnancy tests result in a false positive?
Yes. Pregnancy tests work by detecting the hCG hormone, which is usually only present if you’re pregnant. False positives are extremely rare if you use a valid pregnancy test correctly.
Whenever you see a positive result, whether the test is expired or not, it’s important that you see your healthcare professional.
Key takeaway: Don’t use an expired pregnancy test.
The next time you’re cleaning out your bathroom drawers, check the expiration dates on any home pregnancy tests you may find. Store the tests properly and follow usage instructions for optimal test results. Out with the old, in with the new… and more reliable results!
Related Articles
Sources
- Gnoth C, Johnson S. Strips of hope: accuracy of home pregnancy tests and new developments. Geburtshilfe und Frauenheilkunde, 2014;74(7):661-669. doi: 10.1055/s-0034-1368589. Accessed September 29, 2023. https://www.thieme-connect.de/products/ejournals/abstract/10.1055/s-0034-1368589
- Scolaro K, Lloyd KB, Helms KL. Devices for home evaluation of women’s health concerns. Am J Health Syst Pharm. 2008;65(4):299-314. doi: 10.2146/ajhp060565. Accessed September 29, 2023. https://academic.oup.com/ajhp/article-abstract/65/4/299/5128081?redirectedFrom=fulltext
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