False Positive Pregnancy Test: Reasons & Medications

False Positive Pregnancy Test

Medically Reviewed By
Dr. Sabiha Anjum (Gynecologist/Obstetrician)
View more Gynecologist/Obstetrician Our Panel of Experts

If you are planning to start a family, experiencing morning sickness or nausea and missing your periods will make you happy no doubt, but you need to be sure that you’re pregnant. You may consider a home pregnancy test, a convenient tool, to find out if you are expecting. At-home pregnancy test kids are easily available over-the-counter and are easy to use. Most of these kits include sticks which are designed to detect the presence of the pregnancy hormone — hCG (human chorionic gonadotropin) in the urine, a hormone which rises rapidly when an egg is fertilized. These home pregnancy tests claim to be foolproof, but in rare cases, the results could be off, i.e., the kit may give a false-positive result.

What Is a False Positive Pregnancy Test?

A woman holding a pregnancy test kit

When the pregnancy test indicates a positive result, but you are NOT pregnant, it is referred to as a false-positive pregnancy test.

Causes of False Positive Urine Pregnancy Test Result

Although the chances of a false-positive pregnancy test are rare, it may happen. Here are some commons reasons why the pregnancy test may give you erroneous life-altering news.

1. You Had an Abortion/Delivery Recently

If you had delivered a baby recently or had an abortion or miscarriage in the past eight weeks, your hCG levels will still be high. If you take the pregnancy test during this time, it may show false positive, since the hCG levels in the body drop slowly and gradually after pregnancy ends.

2. You Had a Chemical Pregnancy

A chemical pregnancy is when a fertilized egg stops developing after implantation and never becomes an embryo. Technically, though, you might have been pregnant when you took the test, this pregnancy ends in an early miscarriage. Around 25-40 per cent of pregnancies are estimated to end as undetected miscarriages. Chemical pregnancies end up really soon and most women don’t even realise that they were pregnant. But they can cause the body to produce hCG, which could be picked up in a pregnancy test and thus show a false-pregnancy test.

3. You Have an Ectopic Pregnancy

Ectopic pregnancies occur when a fertilized egg implants itself somewhere other than the uterus. The embryo cannot grow since there is no place for it to thrive outside of the uterus. An ectopic pregnancy is one of the reasons for a false-positive pregnancy test. But an ectopic is a medical emergency. If you suspect an ectopic pregnancy, you must seek medical help.

4. You Have Some Medical Problem

Certain medical conditions such as cancers of the ovary, bladder, kidney, lung, breast and stomach; gestational trophoblastic diseases; ovarian cysts; kidney disease or urinary tract infections; adenomyosis can cause a woman’s hCG to rise and lead to a false-positive test result.

5. You Are Nearing Menopause

Women who transition to menopause often have high levels of hCG. This can cause a false-positive test result in some older women. If you’re nearing menopause and take a pregnancy test, chances are that it will show a false-positive test.

6. Your Test Showed an Evaporation Lines

If you don’t follow the manufacturer’s instructions properly, you might possibly get a false-positive. You’ll have to make sure you check the results within the instructed time frame. Letting the test sit longer than the specified time period can have you confuse the urine evaporation lines for a positive test line.

7. You Have a Defective Pregnancy Test

An expired, or a defective pregnancy test can yield false results. So you must check for a valid test before use.

8. You Took the Test Too Early

Some highly sensitive tests can detect a positive just days after ovulation. Hence, it is recommended that you wait at least a week after a missed period. Testing too early is one of the common reasons for a false-positive pregnancy test.

9. The Urine Sample is Contaminated

If the urine sample contains any impurities like soap or blood, you might read an inaccurate result.

Medication That Can Cause a Pregnancy Test to be False Positive

If you are receiving fertility treatment in the form of shots of hCG or gonadotropins for ovulation, you may get a false-positive test result.

Apart from that, medication like antipsychotics, antihistamines, anti-anxiety medications, diuretics,  medicines for Parkinson’s disease and drugs like methadone, chlordiazepoxide or promethazine can cause false-positive pregnancy tests.

What Is Phantom hCG Test and How Is it Related to False Positive Pregnancy Test?

A phantom hCG is a positive blood pregnancy test with a woman who is not pregnant. Certain chemicals in an individual’s body interfere with the testing kit, causing it to show a false positive.

You may have a reason to check whether you’re getting a Phantom pregnancy positive test if your urine test is negative.

What Is the Reason for False Positive Blood Pregnancy Test Result?

If you’ve realized that you have got your U-check pregnancy test false positive, it is advised to have a healthcare professional confirm with a blood pregnancy test. Blood tests can detect hCG at lower levels than urine tests, and therefore are more reliable as they can detect a pregnancy earlier.

But a qualitative hCG blood test can also be false positive or negative due to some reasons. Some of the reasons of how can you get a false positive pregnancy test are common for urine or blood tests.

Specifically, certain medications (as mentioned above), tumours, ovarian cancer, blood or protein in the urine and a multiple pregnancies cause the presence of high hCG levels in a woman. Besides, chemical pregnancy, menopause and fertility treatment are also some of the causes that can increase the chances of getting a false positive pregnancy test.

If your at-home pregnancy test has read a positive result, it is recommended that you consult a doctor to confirm the result with a blood test. If to your delight, you find out for sure that you are pregnant, you must see your doctor regularly. It is important to take care of your health and undertake early prenatal care under their supervision towards maintaining a healthy pregnancy.

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