I am an LPN (licensed practical nurse), and I am currently employed at a local hospital working in acute/transitional care.
What Kind of Pregnancy Test Should You Buy?
Buying a pregnancy test can be a very exciting and/or nerve-wracking moment in a person's life. Emotions may be running high as you visit the nearest store. To add additional confusion to the situation, most stores offer a variety of options, so now you're faced with a decision. Which one should you buy?
Isn't a pregnancy test a pregnancy test? Is there really a difference? The answer is yes. There are differences between all of the tests on the shelves. Most of us know that prices and sensitivity can vary between brands, but did you know that the colour of the dye in the pregnancy test you select can actually make a huge difference? Learn which colour dye is better and why.
Blue vs. Pink: Which Is Better?
So, should you buy a pink dye or a blue dye pregnancy test? My vote is pink! Here are a few reasons why I think pink dye tests are a safer choice.
Advantages of Pink Dye Pregnancy Tests
- They are less likely to produce an evaporation line (more on this below). Whether or not you are hoping for a positive result, a false positive can be very upsetting.
- Pink lines tend to be easier to see when testing early compared to blue lines.
- First Response brand pregnancy tests are considered by many to be the best and most accurate tests you can buy (the price reflects this, of course), and they use pink dye.
The choice is yours, of course, but my advice would be to purchase a pink dye test. Whether you choose an expensive First Response kit or one of the cheaper dollar store tests, I feel that with pink dye, you are more likely to get an accurate result.
Evaporation Lines and False Positives
A quick Google search reveals that the majority of people opt for pink dye tests over blue. But why? What's the difference? Is it true that a line is a line on a pregnancy test, no matter how dark, light, thick, or thin? Does a second line mean that you are, in fact, 100% pregnant? No! While some of us are veterans at trying to conceive and know all of the ins and outs, many of us are not as familiar with this type of stuff. So why isn't a line a line on a pregnancy test?
What Is an Evaporation Line?
A second line on a pregnancy test does not necessarily mean that its user is pregnant. An evaporation line is a line caused by the evaporation of urine on the test area. Evaporation lines are one of the leading causes of false-positive results in pregnancy tests.
What Causes Evaporation Lines?
An evaporation line may occur if someone waits too long to read their test result. Although the time limit is usually the culprit for creating an evaporation line, it is not always the cause, and it is possible for an evaporation line to develop even within the listed time limit.
How to Prevent Evaporation Lines
So, how do you tell if it's an evaporation line or a real line? First of all, you can use pink dye tests rather than blue dye tests. Blue dye tests are known to be more likely to produce evaporation lines than pink dye tests.
You should also be sure to read your result within the listed time limit. Each brand of pregnancy test should indicate on the box when the test results should be read. It is usually somewhere under 10 minutes. Reading the result after the time listed allows the urine additional time to evaporate on the test, resulting in—you guessed it—an evaporation line. Another way to reduce the risk of an evaporation line is to dispose of any damaged or expired tests. They cannot be trusted!
How to Tell the Difference Between a Positive Result and an Evaporation Line
Study the line closely. Does it have colour to it? Or is it more of a grey-white line or an indent? A positive pregnancy test result should be pink (or blue) just like the control line. It should also run from the top of the test window to the bottom and have the same thickness as the control line. Essentially, the test line should look like the control line, but it does not need to be as dark.
Popular Test Brands
|Pink Dye Tests||Blue Dye Tests|
Clear Blue Easy
Clear Blue Plus
Error Proof Test (E.P.T.)
First Response Early Result
Fact Plus Pro
New Choice (Dollar Store)
Pro Care (Dollarama)
Learn More About Pregnancy Tests
This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.
Questions & Answers
Question: How do I know if I'm pregnant because my pregnancy test had a two-line, and different colors? The first line was color pink and the color of the below line is a blue blur.
Answer: Try reading the instructions on the package again. It depends on the brand.
Shan on October 30, 2019:
Hi I'm i try pregnancy test result is one line is white and one line is red i ask this is a negative or positive??
Shaterrica Johnson on June 07, 2019:
I see one line and you can barely see that Other line
Sunshine on June 22, 2018:
Sorry typo 17th of May
Sunshine on June 22, 2018:
Hi..am 15 days late got my period on the 8th of May..Stopped birth control on the 10th May with diarrhea. On 17th of June spotting 2 days light red and brown and pulling cramping on right lower abdominal..did a test 22nd of June blue dye negative result 2x
Tracy B (author) from Canada on June 17, 2018:
A false negative is more likely than a false positive. With that being said, the blue dye tests are more likely to give you an evap. line. I hope you got it figured out and got the answer you are wanting.
Charlei on June 10, 2018:
So I got a clear blue positive on a blue dye but a negative on a pink dye. Still early my period is not for two days? What do you think? Pregnant or no?
Tracy B (author) from Canada on September 11, 2014:
Thank-you! You learn a lot about pregnancy tests while trying to concieve!
Devika Primić from Dubrovnik, Croatia on September 11, 2014:
Informative and so interesting about these tests. It would be useful for someone planning on a pregnancy.