False Positive Pregnancy Blood Test Results

It takes at least seven days after fertilization for the test to become positive.

False positive pregnancy blood test results.

Taking a home urine pregnancy test. Though very rare a false positive blood test happens with a low positive blood pregnancy test the urine test is negative and there is no pregnancy. Wrong results with blood pregnancy tests a blood test might not detect human chorionic gonadotropin hcg even when a woman is pregnant if the test is done too early. As with urine home pregnancy tests it is possible to end up with false results both negative and positive from a blood pregnancy test.

After an abortion or miscarriage a home pregnancy test may produce a false positive result since the levels of hcg in the body may still be relatively high. First a quick summary. Molecules made by our immune system that identify and neutralize invaders such as bacteria and viruses. If there s a false positive test result the test indicates that a woman is pregnant when in fact she isn t.

A false positive test result a positive human chorionic gonadotropin hcg test result when you are not pregnant can occur for a variety of reasons. Most over the counter pregnancy tests measure the levels of hcg in a woman s urine. Chemical pregnancies are common and often occur for no reason. But they can cause the body to start producing hcg which could get picked up on a pregnancy test and cause a false positive reading.

Intact hcg reduced the number of false positive pregnancy test results from 13 to 1 a 92 reduction 95 ci 64 99 corresponding to a reduction in the false positive rate from 38 95 ci 22 56 to 3 95 ci 1 15. Other medications can also cause false positive pregnancy tests. It may cause a false positive reading on an at home pregnancy test particularly if the test is taken too early. A phantom hcg causes a positive blood pregnancy test without being pregnant.

Human blood normally contains many different types of antibodies.