Yes, Pregnant Tests Do Expire—Here’s What to Know

When it suddenly registers that you might be pregnant, you want a definitive answer right away. But after unearthing an old pregnancy test box that’s been hanging out in the back of your closet, it’s fair to ask: Do pregnancy tests expire?

All my pregnancies have been spaced several years apart, so it wasn’t abnormal for me to have old tests laying around for a while. But the last time I was about to use a vintage test, I noticed that the expiration date stamped on the box had passed. I decided to hedge my bets and use it anyway, but quickly became frustrated when the results were fuzzy and hard to read. So I ended up having to go to the store to buy a new one anyway.

While there’s no real harm in using an old pregnancy test (beyond potential mental distress!), ob-gyns say that the date on the package is there for a reason. So, yes, pregnancy tests do expire, and that means you may not get accurate results if you use one that’s past its prime. Ready to get the full lowdown? Here’s what experts want you to know.

Key Takeaways:

• Home pregnancy tests work by detecting human chorionic gonadotropin (hCG) in your urine. When a test identifies this telltale pregnancy hormone, a reaction occurs where a second test line or—in the case of a digital pregnancy test—the word “pregnant” appears.
• All pregnancy tests do expire at some point. You’ll want to take note of the date on your box.
• Results may not be accurate if you’ve used a test after the expiration date has come and gone.
• Every company’s test has a slightly different shelf life/ lifespan. You’ll want to pay attention to the box. When in doubt, get a new pregnancy test.

Do Pregnancy Tests Expire?

Yes, pregnancy tests aren’t meant to last forever. “They definitely have a shelf life,” confirms G. Thomas Ruiz, MD, lead ob-gyn at MemorialCare Orange Coast Medical Center in Fountain Valley, California.

When Do Pregnancy Tests Expire?

Every company and test is slightly different, making it important to read the label carefully. “Pregnancy tests have an expiration date usually on the outside packaging,” says Meleen Chuang, MD, associate professor at the Department of Obstetrics and Gynecology at NYU Grossman School of Medicine and chief of obstetrics at NYU Langone Hospital in Brooklyn. Some will also state the expiration date on the wrapper that immediately surrounds the test.

What’s the general shelf life of a pregnancy test?

It depends. “The expiration time for a pregnancy test kit is typically between one to three years from the date of manufacture,” Chuang says. “However, the exact time can vary depending on the brand and type of test.”

How to Know If Your Pregnancy Test Has Expired

The only way to know for sure if your pregnancy test has expired is to read the label. “Checking the expiration date printed on the packaging is important prior to use,” Chuang reiterates.

Do Expired Pregnancy Tests Still Work?

If you have an expired pregnancy test, there’s no guarantee that it’ll still work. “The chemical reagent that reacts to hCG starts to break down over time, which makes the test not reliable,” Chuang says. She also points out that damage to the package can interfere with the results.

Do expired pregnancy tests give false positives?

It’s possible for an expired pregnancy test to give a false positive—or a false negative. “You cannot expect a reliable result one way or another if it’s expired,” Ruiz says. That said, Chuang says you’re more likely to get a false negative—where the test says you aren’t pregnant when you actually are.

How Do Home Pregnancy Tests Work, Anyway?

Every home pregnancy test is slightly different, but they all rely on similar technology. Again, home pregnancy tests detect the presence of the pregnancy hormone hCG in urine.

A dye-pregnancy test contains an antibody to hCG and then changes colors when the hormone is detected in urine, Ruiz says. When you pee on a stick or dip it into your urine, the reagent will change color (or make a second line appear) if it detects hCG, Chuang adds. (Digital tests work similarly; the reactionary chemical signals the test to display either the word “pregnant or “not pregnant.”)

How to Ensure an Accurate Result on Your Home Pregnancy Test

Doctors recommend taking a few steps to increase the odds of getting an accurate result on your home pregnancy test:

• Check the expiration date, and don’t use an expired test.
• Wait to take the test until you miss your period.
• Consider taking a test first thing when you wake up (early-morning urine tends to have a higher concentration of hCG).
• Don’t use a damaged test.
• Follow the test instructions carefully.

To Sum It Up

It’s tempting to use an expired pregnancy test to save money—and because it’s there in the moment you want it, but doctors recommend tossing it in the trash and getting a new one. Expired pregnancy tests aren’t accurate, raising the risk of getting an incorrect or unclear result. “This process is stressful enough already,” Chuang says. “Correctly follow the instructions and get peace of mind using a non-expired test.”

Please note: The Bump and the materials and information it contains are not intended to, and do not constitute, medical or other health advice or diagnosis and should not be used as such. You should always consult with a qualified physician or health professional about your specific circumstances.