Blood Tests to Confirm a Pregnancy
Most women will find out if they are pregnant or not by using a home pregnancy test that tests their urine. However, there are sometimes reasons why a blood test might be used in early pregnancy to detect or track the early progress of a pregnancy. How do these tests differ, and why might you need a blood test to confirm your pregnancy?
Home pregnancy tests and pregnancy blood tests are both used to detect hCG in the body. HCG is the hormone that is produced once a fertilized egg implants in the uterus. In early pregnancy, this hormone increases rapidly as the pregnancy develops.
Home pregnancy tests will simply tell you if there is or is not hCG in the urine. They will not give you an accurate look at the specific levels of hCG, or at what rate those levels are increasing.
A blood test will be able to detect exactly how much hCG is present in the blood, and when taken over the course of days or weeks, will be able to indicate if the pregnancy is developing normally.
How can I know if I need a blood test?
Because your care provider will need to order a blood test for you, it is a good idea to discuss with them if you need one. Some providers will order a one-time blood test to confirm your pregnancy after a positive home pregnancy test, while others may not. This will usually depend on their practice and your risk factors.
If you have experienced pregnancy losses, have received fertility treatments, or have other health concerns tied to pregnancy, you may be asked to have early blood tests to record your hCG levels over the course of a few days or weeks.
If you have any concerns about the development of your pregnancy, talk to your healthcare provider. They will be able to help decide on the best course of action in regard to blood tests in early pregnancy.
What should I expect from a blood test in early pregnancy?
A blood test in early pregnancy is performed like any other simple blood test. You will have a small amount of blood collected, and your results will be available after your blood sample has been tested. You might have an appointment after your test to go over the results with your provider, or they may simply call you with an update and any further instructions.
How accurate is a blood test?
Blood tests in pregnancy are about 99 percent accurate. Providers rely on the information they provide to direct further testing or action. If you receive a blood test in early pregnancy, you can be confident that the result is an accurate one.
Would a blood test detect pregnancy earlier than a home test?
Because blood tests are able to detect smaller amounts of hCG than at home urine tests, they are able to detect a pregnancy earlier than a home test. However, you will still need to wait until after implantation to get a positive blood test. You may get an early blood test to detect a pregnancy if you have undergone fertility treatments or are needing to detect a pregnancy very early due to health reasons. Otherwise, a home test is usually the preferred method of pregnancy detection.
Should I get a blood test if I have a negative home test?
If you have a negative home pregnancy test, but still suspect you are pregnant, call your healthcare provider. They will likely order a blood test to confirm your test results. Sometimes, particularly in very early pregnancy on in the case of a pregnancy that is not developing properly, your hCG levels may simply be too low for a home pregnancy test to detect. Getting a blood test can help give you an accurate picture of your pregnancy status and help you decide on your next steps with the help of your provider.
Why shouldn’t I just get a blood test first, and skip a home pregnancy test?
Unless you have a medical reason to be testing for pregnancy very early via a blood test, a home pregnancy test is typically the preferred method for pregnancy testing. Home tests affordable and very accurate, and you will be able to test in the privacy of your own space.
Early detection pregnancy tests can detect hCG in the urine up to 5 days before your missed period, which means that you will not have to wait very much longer to get an accurate result.
There are several reasons that you might need a blood test to confirm or track your early pregnancy. Whether it is to confirm a home test result, or keep careful track of your hCG levels due to medical reasons, blood tests can be a useful tool. Make sure that you consult with your care provider if you feel a blood test would be helpful, but keep in mind that a home pregnancy test is an accurate, quick way to find out if you are pregnant.