Why Is My Pregnancy Test Line Getting Lighter?

Why Is My Pregnancy Test Line Getting Lighter

Published on Feb 26, 2025

Leslie Hughes
Written byLeslie HughesWomen’s Health Writer
Dr. Aditi Neelakantan
Verified byDr. Aditi NeelakantanMedical Practitioner, MBBS

You take the test and anxiously watch the clock until it's time. Finally, it's time to look at the test, and you find that it's positive! You're pregnant!

The excitement floods your system. Then a few days later, you worry it's too good to be true, so you grab another test to confirm.

But this time, you notice the positive test line getting lighter on the pregnancy test. What does it mean?

Before you spiral to the worst scenario, know there are a few reasons why this could be happening. And not being pregnant is only one of them.

We’re here to help you get to the bottom of these lines on a pregnancy test.

Key Takeaways

  • Positive pregnancy test lines get darker as you progress in your pregnancy. This is because of increasing hCG levels.
  • If you’re seeing your home pregnancy test line getting lighter, ask someone else to check it for you. The lightness of these lines can be subjective.
  • Faint positive lines could also mean that your urine is more diluted. Or you could be mixing test brands, you have an evaporation line, or you’ve had a chemical pregnancy.
  • An evaporation line occurs when you leave your pregnancy test sitting out too long. This leaves the salt in your urine behind and also a faint line.
  • A chemical pregnancy is a very early miscarriage because the embryo stops developing.
  • Early pregnancy bleeding happens in 15-25% of pregnant women.
  • This bleeding is spotting or mild and lasts only a day or two.
  • If you experience bleeding that’s more like a period flow after a positive pregnancy test, go to the doctor immediately.

Why Is My Pregnancy Test Getting Lighter?

Questions about home pregnancy tests are normal. Taking multiple tests helps clarify things, but not always.

If you take two tests and the pregnancy test is getting lighter instead of darker, you’re probably wondering what’s going on. Here are some possible causes and what you can do:

CauseWhat you can do
Line eyesHave someone else read the results
Use digital tests
Diluted urineTest first thing in the morning
Mixing test brandsStick to one brand for all tests – buy a multi-pack
Evaporation lineSet a timer according to test directions
Chemical pregnancyReach out to your doctor

You’ve got line eyes

One potential cause for your pregnancy test showing a dark first line and a faint second line is your eyes.

No, you aren’t crazy. And you aren’t alone. Many women who are Trying To Conceive (TTC) experience this.

Sometimes the faint lines are simply your eyes playing tricks on you. Line eyes make it harder for you to read your test results accurately.

Pregnancy tests and their lines are subjective. What one person considers dark may differ from what another person finds dark. Hence, it’s a good idea to ask someone else to take a look at your results, too.

This is where digital tests have an advantage.

Rather than trying to read between the lines (pun intended), you get a clear “pregnant” or “not pregnant” result.

Your urine is more diluted

If your urine is diluted when you take your pregnancy test, this can decrease the concentration of the pregnancy hormone, hCG (Human Chorionic Gonadotropin). Which means the pregnancy test reads lower levels of hCG in your urine.

And that may give you a lighter pregnancy line.

To avoid this, test your first urine in the morning. Since your urine is more concentrated in the morning, it will more accurately detect the hCG hormone.

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You’re mixing test brands

We love the convenience of at-home pregnancy tests, but they vary slightly in their design.

If you’re taking multiple tests, stick with just one brand. Different brands may:

  • Have different levels of sensitivity
  • Use different types of dye
  • Incorporate different manufacturing

If you’re taking multiple tests, stick with just one brand. Buy a multi-pack at the store and only compare tests from the same brand.

You have an evaporation line

We all have moments of forgetfulness.

However, forgetting to check your pregnancy test results at the right time can cause the pregnancy line to get lighter.

If the test sits out too long, the urine evaporates, leaving the salt in your urine behind. And along with it, a very faint line on your pregnancy test.

But sometimes it can be hard to tell whether that faint line is an evaporation line or a faint positive pregnancy test.

Here are a few differences between a faint positive line and an evaporation line to help you distinguish:

Faint Positive LineEvaporation Line
ColorThe same color as your control line (usually pink)Colorless or gray
TimeAppears after about a few minutes (read your test instructions for the exact time to check test results)Appears when a pregnancy test has been left out too long (several minutes beyond test instructions)
MeaningFaint positive line = positive result. If you’re still doubting, try re-testing tomorrow for a darker line.Evaporation line = meaningless. They only show up on negative tests. Throw away your test and use a new one.

To help avoid confusion with a faint line, set a timer for the amount of time specified in your test directions to wait. Check the results immediately.

You’re having a chemical pregnancy

So you’re doing all of the following:

  • Asking someone else to read your test results
  • Testing first thing in the morning
  • Using a single brand for testing
  • Setting a timer for your results

But you’re still seeing a lighter line. Your hCG levels may be dropping, which can be a sign of a chemical pregnancy. This type of miscarriage happens on or before the fifth week of gestation.

You may also get a miscarriage that looks and feels like your period, but is delayed, heavier than usual, and has clots.

The halting of embryo development is what causes the drop in hCG levels. And this all happens before the fetus is even visible on an ultrasound.

Chromosomal abnormalities are often to blame for a chemical pregnancy.

Reach out to loved ones for support during this time. Also, consider looking to the Inito Support group to find women who can relate to what you’re going through.

Learn more: 6 Tips to Get Pregnant After Chemical Pregnancy

Should Pregnancy Test Lines Be Getting Darker?

In short, yes. Your test lines should become darker as you progress in your pregnancy (at least until the first trimester).

This happens thanks to Human Chorionic Gonadotropin (hCG), a.k.a. the ‘pregnancy hormone’.

And at-home pregnancy tests are used to detect your urine hCG levels.

Here’s a look at how your hCG levels change throughout pregnancy and why that causes a pregnancy test line progression.

Pregnancy TimelinehCG Values
First 6/7 weeksDouble every 48 hours
6/7 - 10 weeksDouble every 4 days
10 weeksReach their peak
> 10 weeksHold steady or decline

The ‘hCG doubling time’ during the first few weeks is when your hCG typically doubles.

As your pregnancy progresses, the doubling time slows down. And once you reach your peak hCG levels around 10 weeks, they either plateau or decline.

At-home pregnancy tests don’t give you the exact hCG level. They can only detect if it’s above a certain threshold.

And, as a general rule, the darker the line on the test, the more hCG is in your urine.

A.k.a. the further you are in your pregnancy, the more your hCG levels increase. This translates to a darker indent line on the pregnancy test.

Now, let’s discuss what happens if you see a positive test followed by bleeding.

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What if I Get My "Period" After a Positive Pregnancy Test?

There are varied reasons behind getting your period after a positive pregnancy test.

For starters, early pregnancy bleeding is more common than you think. In fact, it happens in 15-25% of women.

However, if you’re concerned, consult your doctor. It could mean more.

Chemical pregnancy. As we talked about earlier.

Ectopic pregnancy

Ectopic pregnancy is when implantation occurs outside of the uterus. This can happen in the fallopian tubes, ovaries, cervix, or the abdomen. And it unfortunately results in a non-viable pregnancy.

Symptoms of an ectopic pregnancy include:

  • Heavy bleeding
  • Clots
  • Severe nausea
  • Abdominal pain

If you’re experiencing these, seek emergency care immediately.

Learn more: Can You Have a Period and Be Pregnant?

When Do I Need to See a Doctor?

Tell your healthcare provider about your positive pregnancy test.

You’ll want them to confirm your pregnancy. Plus, they’ll give you some prenatal advice to kick this pregnancy off the right way. Your doctor’s office will also schedule follow-up care and chat about any questions or concerns you may have.

If you’re TTC and experiencing pregnancy test line confusion, we hope this article will help. It’s important to remember that both faint and dark positive lines exist.

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Leslie Hughes

Leslie Hughes

Women’s Health Writer

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