False-Positive Pregnancy Test Results: Causes and What to Know

Key Takeaways

• A pregnancy test may cause a false positive if it detects hCG in your body even though you are not actually pregnant.
• A chemical pregnancy is different. A pregnancy does occur but stops progressing shortly after, and unlike false positives, chemical pregnancies are fairly common.
• Common false positive pregnancy test causes include a recent pregnancy, fertility medications, certain health conditions, evaporation lines, an expired test, or user error.
• If you get an unexpected positive result, retake the test, keep taking any prescribed medications, and check in with your doctor.
• Seek emergency care right away if you experience heavy bleeding, intense pelvic or abdominal pain, or dizziness.

The Reasons behind False Positive Pregnancy Test Results

Few things can change your mood as quickly as a positive home pregnancy test. If you’ve been trying to conceive, you may feel overjoyed. If you weren’t expecting a pregnancy, the same two lines can bring a very different reaction. And sometimes, those two lines don’t mean there’s an ongoing pregnancy at all.

False positive pregnancy tests are rare, but they can happen. Pregnancy tests react to human chorionic gonadotropin (hCG), a hormone produced during pregnancy. In some situations, hCG can be present even when you are not currently pregnant. There are several reasons for false positive pregnancy tests, and knowing what they are can help you understand an unexpected result.

At Almara’s maternity clinic in Woodbury, MN, we help women make sense of unexpected pregnancy test results and understand what to do next. This guide looks at the common causes of false positives and when to seek medical care.

How Do Pregnancy Tests Work?

Once a fertilized egg attaches to the walls of the uterus, the body starts producing hCG. And home pregnancy tests detect it. Levels of this hormone rise quickly in early pregnancy, which is why urine tests can usually pick it up once it crosses a certain threshold.

The accuracy of your result depends on the test itself and the timing of when you take it. A few things to keep in mind:

• Read the manufacturer’s instructions before interpreting a positive result
• Pay attention to the specific time window recommended for reading the outcome

False Positive Pregnancy Test vs. Chemical Pregnancy: What Is the Difference?

More than 45,000 women visit Almara’s clinics each year for a wide range of concerns, including confusion around unexpected test results. It is common for a false positive to get mixed up with a chemical pregnancy, but the two are not the same thing.

A chemical pregnancy happens when an embryo implants and produces enough hCG for a positive test result, but the pregnancy stops progressing shortly after. Signs of a chemical pregnancy often include:

•  A positive test followed by a negative one
• A period that arrives later than expected
• Cramping
• Bleeding
• Declining hCG levels on repeat testing

Technically, this is not a false positive pregnancy test, since a pregnancy actually began. Chemical pregnancies are also far more common than true false positives and are usually caused by random chromosomal abnormalities that are entirely outside anyone’s control.

What Causes a False Positive Pregnancy Test?

A handful of factors are known to trigger an inaccurate positive result:

Recent Pregnancy

This is one of the most frequent false positive pregnancy test causes. If you recently gave birth, had an abortion, or experienced a miscarriage, hCG can stay in your system for several weeks afterward. That means a positive result can still show up even though the pregnancy has already ended.

Fertility Medicines with hCG

Some fertility medications used to trigger ovulation contain hCG themselves, which can lead to a temporary positive result. If you are on one of these medications, ask your specialist about the best time to test to avoid confusion.

Certain Health Conditions

In rare cases, conditions like ovarian tumors or related growths can raise hCG levels enough to cause a false positive. If you keep getting positive results without an actual pregnancy, it is worth getting evaluated by your doctor.

Evaporation Lines

As urine starts drying up on the test, an evaporation line might appear. It’s usually faint and gray or colorless. And if you view the result after the suggested reading period, it might seem like a positive.

Expired Test

Using an expired test is one of the typical reasons for false positive pregnancy test results. So, check the packaging, expiration date, and test condition first. Use a new test if something’s off.

User Mistake

If you don’t stick to the test instructions closely, the result is likely to be inaccurate. For instance, you might:

• Use too little or too much urine
• Hold the test incorrectly
• Interpret the outcome outside the timeframe advised

What Should You Do If You Think You Have a False Positive Pregnancy Test?

If a positive result leaves you with more questions than answers, these steps can help:

Repeating the Test

Use another test (from another brand or package) and follow the instructions exactly. Since the urine you pass first in the morning is typically more concentrated, using it might ensure more accuracy.

Carrying On with Prescribed Medicines

If you are on fertility medication or any other prescription, do not stop taking it based on a test result alone. Talk to your doctor first.

Contacting Your Doctor

Your healthcare provider will probably recommend a blood hCG test or ultrasound to confirm pregnancy. They might also repeat the hCG test to monitor the changing levels of this hormone.

• Seek medical attention right away if your test is positive and you are also experiencing:
• Severe pelvic or abdominal pain
• Shoulder pain
• Heavy vaginal bleeding
• Significant weakness
• Dizziness

Facing a False Positive Pregnancy Test Result with Confidence

It is natural to have a lot of questions after an unexpected positive result. False positive pregnancy tests are not common, but they do happen for a range of reasons. Knowing what usually causes them can help you feel steadier and better prepared to figure out what comes next.

Talk to Almara Clinic About Your False Positive Pregnancy Test Result

Almara’s board-certified gynecologists understand how confusing and unsettling a false positive can feel. We can confirm whether you are pregnant with accuracy, help explain what may have caused the unexpected result, and guide you through the next steps with genuine, compassionate care.

Reach out to us online or visit one of our clinic locations.

You can also write to us at info@helloalmara.com.

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