False Negative Pregnancy Test

What happens when your period is late and you are experiencing just about every sign of pregnancy, but the pee stick indicates a negative?

I know, I know…. You probably have a whole stash of sticks just waiting to be peed on, but there’s only so much pee. 

You’re convinced you’re pregnant but which do you believe?

The negative sign on the pregnancy test or the fact you just threw up your breakfast? 

Can you get a false negative pregnancy test? Read on to find out more.

Can you get a false negative pregnancy test?

Unfortunately, yes you can. A false negative pregnancy test is more common than a false positive. 

Home pregnancy tests work by detecting a hormone called human chorionic gonadotropin (hCG) in your urine.

hCG is the hormone that’s produced when you’re pregnant and it’s the key to your home pregnancy test giving a positive reading. 

All the symptoms you’re experiencing are a result of the rising levels of hCG.

Click here to find out more about hCG and pregnancy symptoms. 

There are 3 main reasons you might get a false positive pregnancy test:

1. You are so eager to see the result you don’t allow enough time for the correct result to appear, or you wait too long. Always follow the instructions on the box and read the results within the recommended time period.
2. You take a test too soon after missing your period. Urine pregnancy tests rely on hCG in your urine. Test too early and the amount of hCG in your urine isn’t detectable. As many as 9 out of 15 women will get a false negative until seven or eight weeks of pregnancy. 
3. You’re so eager to pee on a stick that you drink a few litres of water to fill your bladder. Or you take the test late in the day. Your urine might be diluted making the hCG levels undetectable. The best time to do a pregnancy urine test is when you first pee in the morning. 

Although home pregnancy tests are quick, easy and convenient, it’s important to use them correctly. The accuracy of the result is dependent on following the instructions provided. 

Some urine tests will advise you to pee directly on the stick, by holding the stick under the stream of pee.

Others will instruct you to pee into a cup and dip the stick in for a certain amount of time, or to collect pee from the cup, using a provided dropper, and drip it onto the stick.

Follow the instructions carefully, and wait for the recommended time for the result to appear. 

All the tests will tell you how long to wait before checking the result and how to interpret what you see on the stick.

If you get a negative result and you’re convinced that you’re actually pregnant, the next step is a trip to your local doctor’s office or lab for a blood test. 

Two possible outcomes: you’re not pregnant and your period is late for another reason that probably needs attention.

Or you are pregnant but the level of hCG isn’t yet detectable in your urine. Your doctor will do a blood test to confirm. 

How common is a false negative pregnancy test? 

A study in the US shows 5% of standard pregnancy tests produce a false negative result up to 5 weeks of pregnancy and more.

Can you still be pregnant and get a false negative pregnancy test?

Yes, you can. A false negative pregnancy test is common. Although most home pregnancy tests advertise themselves as being 99% accurate, they rely on detectable amounts of hCG in the urine to give a reliable result.

Used incorrectly, used past the use-by date, or even used too early (after missing your period) are all reasons for a false negative.

Not enough pee or too much pee can also produce a false negative.

Even though the test is 99% accurate, the conditions need to be optimal for it to work to that standard. 

Pregnancy blood test 

There are two different types of blood tests used to test for pregnancy. 

If you just want a simple ‘Yes I am pregnant’ (or ‘No, I am not’) answer then request a qualitative hCG blood test.

This test can confirm pregnancy as early as 10 days after conception, as it tests for the presence of hCG in the blood.

If hCG is present, the test indicates a positive result (BFP or big fat positive).

If you get a negative blood test and feel it might have been done too soon, your doctor will repeat the test after 48-72 hours. 

For a bit more detail and an indication of how pregnant you are, then request a quantitative hCG test (also called beta HCG).

This test measures the exact amount of hCG in your blood and the levels fall within a range that indicates how many weeks pregnant you are, according to the normal range.

The levels double every 48 hours after conception and rise consistently until about 10-12 weeks of pregnancy.

Your doctor might also request this test to rule out an ectopic pregnancy or to determine whether you’ve experienced a miscarriage. 

An hCG level of less than 5 mIU/mL is considered negative for pregnancy, and anything above 25 mIU/mL is considered positive for pregnancy.

An hCG level between 6 and 24 mIU/mL is considered a grey area, and you’ll need to be retested to see if your levels rise to confirm a pregnancy.

What else can cause false negative results? 

There are certain medications that can influence the results.

In any case, it is advisable to consult with your doctor regarding your pregnancy if you’re on any of the medications listed below:

• Psychiatric medications such as anti-anxiety (Xanax and Valium), and antipsychotic prescriptions (clozapine or chlorpromazine)
• Diuretics
• Methadone
• Anticonvulsants
• Medications prescribed for Parkinson’s disease
• Antihistamines
• Barbiturates.

False negative but still feel pregnant?

As mentioned above, there are at least 10 physical symptoms you could experience that indicate you’re indeed pregnant, despite a negative home pregnancy test:

1. Sore tender breasts and sensitive nipples 
2. Fatigue
3. Insomnia
4. Nausea 
5. Vomiting 
6. Food aversions 
7. Sensitivity to smells 
8. Peeing frequently 
9. Headaches 
10. Feeling bloated and crampy. 

Check out Pregnancy Symptoms – 16 Early Signs You Might Be Pregnant for more information. 

Always trust your instinct. If you feel you’re pregnant, then schedule an appointment to have a blood test. It’s a more accurate method and will put your mind at rest.