What Does an Invalid Pregnancy Test Mean?

So, you’ve peed on a stick, and followed all the instructions carefully, but you’ve had an invalid pregnancy test result… Firstly, we know how frustrating this can be. 😖

But, what does your invalid result mean? Could it be a positive result? How long after a pregnancy test is it invalid?

We’ve got you covered. Let’s deep dive into the world of invalid pregnancy tests to get you clued up before your next one.

In this article: 📝

What is an invalid pregnancy test?

An invalid pregnancy test shows you that, for some reason, the test hasn’t worked. This could be a negative result when you’re actually pregnant, a positive result when you’re not, or when the test has failed — showing no control line, or broken lines.

So, first off, what does an invalid pregnancy test look like? If your test comes back without the control line, that’s a clear sign your test hasn’t worked. It could also be incomplete vertical lines on dye pregnancy tests.

An invalid pregnancy test can also mean it’s showing a negative result when you’re actually pregnant, which is more common in the early stages of pregnancy, or vice versa (false positives). On digital pregnancy tests, it may also come up with an error.

What if no lines show on a pregnancy test?

No lines — well, no control line, to be more specific — is a sign that your test hasn’t worked. This could be because the instructions weren’t followed carefully enough (for example, some need you to lay the test down flat straight away after urine was applied), or the test could be faulty.

Let’s explore together what could cause an invalid pregnancy test. 👇🏻

Why would a pregnancy test be invalid?

From misreading the instructions to expired tests, there are many reasons why a pregnancy test result can be invalid:

• 💧 Urine sample: Not enough urine, or even too much urine, can cause an invalid result. Be sure to read the instructions carefully, whether you’re peeing on the test directly, or dipping the test into a cup of urine.
• ❌ Faulty tests: Sometimes, you can stumble across faulty or damaged tests. You’ll be able to tell if it’s faulty if the control line doesn’t appear when you’ve taken your test. In some cases, you may be able to get your money back!
• ⌛ Expired pregnancy test: Did you know pregnancy tests can expire? They typically last around 2-3 years from their date of manufacture (not the date you bought it), but vary between brands. So, keep an eye out for this if you’ve got lots stored in the cupboard!
• 💦Splashing water: So, does pouring water on a pregnancy test make it invalid? Short answer — it might. Even the smallest splash of water on your test could invalidate it, as it could cause an evaporation line to appear, which could be mistaken for a positive result (more on this later 👇)! So, be super careful around the faucet when you’re preparing your test.
• ⏲️ Reading your result too late: Remember, pregnancy test results are only accurate for a short period of time. Sometimes that’s five minutes, sometimes that’s 10… but if you’re reading your result 30 minutes later, it’s going to be invalid.

🔍 Read more: What Not to Do Before a Pregnancy Test

Can an invalid pregnancy test be positive?

An invalid pregnancy test may appear to be a positive result. But let’s take a beat — because this could be a false positive.

Some of the reasons why false positives might happen on are:

💊 Medication interference: Certain medications can produce a false-positive result. This includes some antihistamines (such as promethazine), high blood pressure medications, and more. Check in with your doc if you’re taking any kind of medication when taking pregnancy tests — or whatever point you’re at on your TTC journey. 🫥 Evaporation lines: Again, this could produce a false-positive. Evaporation lines are caused by the urine drying after a negative test, rather than from hCG being detected. 🫶 Recent birth or miscarriage: If you’ve given birth recently, experienced pregnancy loss, or terminated a pregnancy, it can take a while for your hCG levels to return to zero — typically taking from one to nine weeks on average. This means, if you retest too soon, you may see a positive result. 👶 Fertility boosting medications: Such as Pregnyl, Profasi, Novarel and Ovridel can also cause false pregnancy test results — which is good to note if you’re using these to try and conceive.

Of course, if you’ve had user error issues (such as splashing water or not reading the instructions correctly), an invalid pregnancy test could actually be a positive test — but the only way to be sure of that is to test again.

Can an invalid pregnancy test be negative?

In some cases, an invalid pregnancy test could produce a false-negative result. So, when would this happen and why?

⏰ Testing too early: Testing too early can result in a false-negative. Pregnancy tests check for the hormone hCG in your urine, and in early stages of pregnancy, this may not be high enough yet to detect it. 😴 Time of day you’ve tested: Another potential false-negative could happen from testing at night, or during the day when you’ve drunk lots of water. Water dilutes your urine, making it harder for tests to pick up hCG, so the best time of day to test is first thing in the morning.

Similar to the above advice, user error issues or faulty tests could provide a negative result when you actually are pregnant, and vice versa — but the only way to be sure is to retest.

How long after a pregnancy test is it invalid?

Most pregnancy tests recommend you should stop reading the result after 10 minutes. But, this can vary by brand — some are 10 minutes, but some are 5, and some can be up to 15 minutes. The best way to know is to thoroughly read the instructions before you get going, and set your timer on your phone so you don’t forget. ⏲️

And, remember, if you read the results of a pregnancy test after this period of time, the results will be invalid. ❌

An evaporation line could appear, which could show a positive result when the test was actually negative. Discard all tests after their allocated time windows and, if you’re still not sure about your result, take another test to be sure.

Can you use an invalid pregnancy test?

In short — no, you shouldn’t use an invalid pregnancy test. Steer clear from reusing any pregnancy tests. ❌

Especially if this test is invalid, as this could be due to expired tests, faulty tests, or user error. Using any invalid pregnancy test won’t produce an accurate result — so, save yourself the time and emotional energy, and head to the drugstore to pick up a new one.

What to do if your pregnancy test is invalid

Short answer? Test again. 🤷‍♀️

We understand how frustrating this can be, especially if you’ve been waiting to test. And pregnancy tests aren’t cheap! 💰

So, head back to your local drugstore and pick up another test as soon as you can. It’s also worth familiarizing yourself with the instructions thoroughly again, just to make double sure you’re doing the test right.

But, if you have two invalid pregnancy tests in a row, or multiple, be sure to consult your healthcare provider for guidance. And, of course, any positive result should always be checked by your doctor straight away. 🤰

Looking for some more support and advice from other women who are trying to conceive? You’re always welcome to join our Peanut Community — we think you’ll fit right in.