Are Pregnancy Blood Tests Ever Wrong?

It can be difficult when you are trying to become pregnant and you cannot get a positive result on either a home pregnancy test or a blood test. Many women start to question just how accurate these tests are and whether they are wrong, and for good reason. It’s said that home pregnancy tests are only about 97% accurate, so what is the margin of error for the blood tests? Experts suggest that blood tests for pregnancy are more than 99% accurate, meaning your chance of receiving a wrong answer is slim, but it does happen.

Generally, blood tests for pregnancy are more accurate than home pregnancy tests. The reason for this is that there is less risk for human error. Unfortunately, pregnancy blood tests can be wrong, although it is much more uncommon than getting a false positive or false negative with a home test. Luckily, the test is neither hard to order or perform so if your doctor doesn’t like the result he or she can simply order a new test to double check the results.

A wrong answer can be the result of many things. If the hCG count is high it may be the result of a tumor, the death of a developing fetus, multiple pregnancy, ovarian cancer, it often happens in a completely normal pregnancy, blood or protein in the urine, and certain medications. If the hCG count is negative or low it could be the result of an ectopic pregnancy, a miscarriage, or recent abortion. Of course, there is no real “normal” as each pregnancy develops just a bit differently than all others, but there is a normal range that your doctor will use to help determine how well your pregnancy is progressing, or if you are pregnant at all.

A common reason for a false negative is simply testing too early. Often doctors will order the test a couple days too soon because the woman is anxious to see if she is pregnant. Most women will receive a negative hCG result less than seven days after fertilization, and some women won’t test positive until more than 10 days after fertilization. If the doctor and the woman have not been able to pinpoint the exact date of fertilization, the doctor typically will wait longer instead of guessing and increasing the chance of a false negative.

So, pregnancy blood tests can be wrong. It’s not all that common, and they are more reliable than your standard home pregnancy test. But, your results are all about timing and the lab that runs your test. If one thing is off, your pregnancy blood test result could be wrong. If you and your doctor don’t like the result, you can always run the test again, so don’t get down if you don’t get the result you expected.

Understanding Chemical Pregnancy

Many women have never heard the term chemical pregnancy until a doctor uses the term with them. Chemical pregnancy is a technical way of referring to a very early miscarriage. With the more sensitive pregnancy tests now on the market, a woman can get a positive test result before her period is due, but a miscarriage occurs before a doctor is ever able to detect a heartbeat or see the baby on an ultrasound. While the early test results are great for some, they mean that many women are feeling the loss of a baby that they might not have ever known about had it not been for the early pregnancy test.

Luckily, most chemical pregnancies occur without the mother knowing that she was ever pregnant. Despite the term not being well known, chemical pregnancies are very common, as some experts believe that up to 60% of first pregnancies end in a chemical pregnancy without the mother ever knowing that she would have tested positive for pregnancy! This is sort of disturbing on one hand, that so many women have been pregnant without ever knowing it, but at least most of those women do not have to go through life wondering what went wrong, and feeling the loss for what would have been their child if it had continued to develop.

Many women feel angry, or feel guilty and think they could have done something to prevent the chemical pregnancy, but this generally is not true. A chemical pregnancy is usually due to a chromosomal issue while the fetus is developing, problems with the placenta, uterine abnormalities, low hormone levels, luteal phase defect, or even certain infections. Most of these issues are not within the woman’s control.

There is no way to prevent a chemical pregnancy, although if a woman continues to experience them her doctor will likely investigate and see if there isn’t an aggravating factor that is forcing the early miscarriage. Many doctors have had luck treating their patients that suffer from multiple chemical pregnancies with vitamin B6, baby aspirin, and progesterone cream. If the doctor finds an infection that has caused the chemical pregnancy, he, or she will likely treat it aggressively with antibiotics in the hopes that a future chemical pregnancy can be avoided.

There is no way to determine how many chemical pregnancies a woman might experience during her life, but the chance that everyone woman will have a chemical pregnancy experience is very real. While it is not something that anyone wishes for, perhaps it is our bodies’ way of taking care of a pregnancy that wouldn’t have been healthy, and allowing us to try again for a healthy pregnancy as well as a healthy baby! Most women that experience a chemical pregnancy go on to have completely normal, healthy pregnancies.


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