Ultrasound accuracy in dating pregnancy
The abnormal pregnancy makes lower levels of HCG, which might be slow to detect.The HCG level can subsequently increase and become detectable though more slowly than with a normal pregnancy.See your doctor if you have heavy or prolonged bleeding or pelvic pain for more than two weeks after a miscarriage or an abortion.Pseudocyesis is a false pregnancy, but the afflicted women are mistakenly convinced they are pregnant.A conception in the uterus that is lost in the early days of implantation, such as a chemical pregnancy, might initially give a positive test.When the pregnancy becomes nonviable, usually because of the failure of implantation, the low level of HCG might still be detectable on a blood test for a short while.Current pregnancy tests are accurate, but there are a few reasons why the results can be wrong.Inaccurate results can arise due to a number of factors and are more likely with home urine pregnancy testing than with a blood test.
An ultrasound exam will show the absence of a baby.
It is more common to have a false negative result than a false positive one.
The following are the main reasons for an inaccurate pregnancy test result.
According to the American College of Obstetricians and Gynecologists, antibodies and other factors in your blood can interact with the test antibodies in a pregnancy test.
This interaction can result in a falsely positive blood pregnancy test.
When a normal pregnancy is not apparent, the situation might lead to extensive evaluation to find the source of the HCG and cause unnecessary treatment, according to the Handbook of Clinical Laboratory Testing During Pregnancy (page 31 to 32).