Home » False-Positive Pregnancy Test – Possible Reasons

False-Positive Pregnancy Test – Possible Reasons

A false positive pregnancy test can be frustrating if you’ve been struggling with infertility. A false-positive pregnancy result occurs when the test indicates you’re pregnant even though you’re not. This mostly happens when using pregnancy test kits at home.

When using a pregnancy test kit at home, you are looking to detect a pregnancy hormone, human chorionic gonadotropin (HCG), which is present in the early stages of pregnancy. However, there are various reasons your results can be false-positive. Therefore as a woman, you are advised to seek confirmation from a doctor.

 

False-Positive Pregnancy Test

What Causes Pregnancy Tests to Give a False-Positive Result?

There are varying reasons a pregnancy test kit can give a false-positive result. However, to ensure accurate results, you must take a pregnancy blood test at the hospital for guaranteed results. Some of the reasons for a false positive include:

 

Expired Test Strip

When buying a pregnancy test kit, always check for the expiry date. This is because an expired test kit might give two red lines. Indicating you are pregnant even when you aren’t. It can lead to a false negative.

Medication

A variety of medications can increase the levels of HCG in your system such that when you take the test, you will get a positive result. Some of these drugs include:

Fertility Medicine                                            

Fertility medicines are at the top of the list. This is because hCG shots help trigger the follicles to release mature eggs. And since the kit is set to detect high levels of Hcg, it will cause a false-positive reading, especially if you take the test too early.

Some of the fertility medications that will result in a false-positive include:

  • Ovidrel
  • Profasi
  • Pregnyl
  • Novarel

Other medications that can trigger HCG in your system and lead to a false positive result include:

  • Antipsychotics medications, such as chlorpromazine and clozapine
  • Parkinson’s disease medications
  • Anti-anxiety drugs, such as Xanax and Valium
  • Diuretics, including furosemide (Lasix and Diuscreen)
  • Methadone
  • Anticonvulsants, such as phenobarbital
  • Antihistamines

Medical Conditions

Various medical conditions can also lead to a false-positive pregnancy result. Many ailments can increase HCG levels in your body, leading to a false positive result. These include:

  • Ovarian cysts
  • certain cancers
  • kidney disease
  • Hormonal disorders, especially during menopause or peri-menopause, trigger high levels of hCG enough to cause a positive reading on some home tests. UTI (Urinary Tract Infection)
  • Chemotherapy

Letting it Rest for Too Long With the Urine

You must follow the instructions when taking a pregnancy test home to guarantee correct results. Some brands suggest dipping the stick in urine for 10 minutes, remove and set it aside. Ensure you don’t leave the test strip in the urine too long. It could invalidate the results because the evaporation lines could appear falsely, indicating pregnancy hormone detection.

Testing at Temperatures Below 36° F or 86° F

Extremely low or high temperatures make it impossible for any liquid sample urine included to register with most commercial kits accurately. Therefore, if you want to take a pregnancy test, ensure that the test kit and the urine are stored at room temperature. And do not drink a lot before the test, as it could affect the concentration of pregnancy hormones in your urine.

Biochemical Pregnancy

A biochemical pregnancy happens when a chemically fertilized egg, or embryo, fails to implant or grow. It’s impossible to detect the pregnancy through ultrasound; however, a pregnancy test kit picks the high HCG levels, thus leading to a false-positive result.

It’s tough for an individual to know they have a chemical pregnancy without testing as it has few symptoms. Although the cause of chemical pregnancy is unclear, many assume it may be due to chromosomal problems in the developing fetus. And most often, they go undetected.

Ectopic Pregnancy

Ectopic pregnancy is when the fertilized eggs implant themselves outside the uterus, mainly in one of your fallopian tubes. This type of pregnancy cannot survive; it’s detrimental to the mother.

The fallopian tube is narrow, so it’s constricted when the fertilized egg develops. It can eventually burst if not removed promptly, and excessive bleeding can result in the mother’s death. Therefore, if you have pregnancy symptoms and notice the following symptoms,  consult your doctor, as it could be a tubal pregnancy.

  • Dizziness
  • Pressure on your rectum
  • Pain on one side of your abdomen
  • Extreme pain in the pelvis, neck, or shoulder
  • Light to heavy bleeding

Ectopic pregnancy is not unheard of, and some of the risk factors include:

  • History of uterine problems
  • History of uterine infections
  • Scar tissue or inflammation in your fallopian tube
  • Fallopian tube anomalies
  • Infertility treatments
  • Past ectopic pregnancies

Note: Ectopic pregnancies can also occur in your cervix or abdominal cavity.

Molar Pregnancy                                   

Although rare, molar pregnancies are known to lead to a false-positive result. A molar pregnancy occurs during the early stages of a pregnancy, where the fetus develops abnormally. Most molar pregnancies result in a mole or a cluster of abnormal cells forming a cyst.

It is also called a gestational trophoblastic disease, whereby abnormal cells grow inside the uterus instead of an embryo forming after conception. Oddly enough, though, these abnormal cells continue producing hCG hormone levels similar to those found during normal pregnancies leading many astray with false positive readings.

Although this doesn’t pose health risks for mothers, You must seek medical attention so doctors can take preventative measures against further development.     

Recent Miscarriage or Abortion           

If you’ve recently experienced a miscarriage or abortion, you’ll likely have traces left over hCG hormones lingering within your body. Therefore, if you take a pregnancy test weeks after your miscarriage, you’ll get a false-positive reading.

That’s why women are advised to avoid taking pregnancy tests soon after a miscarriage. This is because their bodies undergo so much stress after a pregnancy loss. Therefore they should give their bodies time to heal.                                

Evaporation Lines                                     

When taking a pregnancy test, ensure you have all the information, such as how long to dip the strip in urine and how many minutes to read. You must also be aware of the color of the lines.

When there is more moisture in the air, your test strip might get what is referred to as evaporation lines. This usually happens when one line is bright and the other is faded. The faded line may represent an early pregnancy or might be an evaporation.

Contaminated Urine Sample

Ensure the collecting container is clean and rinsed off all the soap and detergent when collecting your urine sample. Failure to do this will contaminate your urine sample, leading to a false-positive result.

Pituitary HCG

Your pituitary gland produces minute amounts of HCG. Therefore, if you are above 40 and get a positive pregnancy result, you can blame it on your pituitary.

Test Strips Were Previously Exposed to Moisture, Heat, or Direct Sunlight    

Pregnancy test strips are very sensitive and stored correctly in their original packaging. However, when exposed to moisture, heat, or direct sunlight at any point before use can render false results that can’t be trusted. So when buying, ensure that the packaging is not tampered with and that they were not exposed to heat or direct sunlight.

 

How to Take a Pregnancy Test?

Check expiration dates before purchasing the pregnancy testing kits because some brands won’t yield accurate readings after a specific time. Then you must read the information on the pregnancy kit packaging carefully and ensure you understand before taking the test.

Step-by-step process of taking a pregnancy test

  • Remove the test strip from the plastic covering
  • Then, sit on the toilet, start urinating, and place the absorbent tip underneath your urine stream for about 10 seconds.
  • Alternatively, urinate into a cup and dip the absorbent tip for about 10 seconds.
  • Then lay the strip on a flat and dry surface and wait for about 5 minutes, then take the reading.

Note: Do not leave the strip too long, as it could get evaporations lines, leading to a false-positive.

 

What are the Possible Outcomes?

When taking a pregnancy test at home, you will possibly have three outcomes:

Positive: This indicates that you are pregnant and will see two lines( one for the control and the other for the test). The color of the lines depends on how early you did the test. As such, they may be bright or faded.

Negative: It indicates that you are not pregnant, and only one line is visible. In this result, the test line is not present.

Invalid: The test is invalid if the control line is not visible. It doesn’t matter if the test line is present; the test will still be considered invalid. And the best option is to take a new test.

 

How do You Ensure that the Pregnancy Results are Accurate?                            

Although rare, to avoid getting false positive test results when using at-home pregnancy test kits, it’s recommended that you use at least two pregnancy kits.

Using different brands to increase the likelihood of positive results would be better. A pro tip, take the test early in the morning as the HCG levels peak. Also, taking the test a week or two after you have missed your period is best.

 

Final Thoughts

Although rare, false pregnancy test results occur and most often could be due to a medical condition, user error, medication, or expired test strip. Therefore, it’s best to consult your doctor after taking a pregnancy test at home. They will conduct a blood pregnancy test and an ultrasound to ensure it’s not an ectopic pregnancy.

 

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.