Difference Between Home and Lab Pregnancy Tests
There are two types of pregnancy tests. One uses a urine sample and the other uses a blood sample. Both these tests detect the presence of human chorionic gonadotropin (hCG) hormone. This hormone is produced after the embryo attaches itself to the lining of the uterus. Its levels in the body increase rapidly during the first few days of pregnancy.
The buildup of this hormone in the blood and urine is a confirmation of a pregnancy and is responsible for many of the classic symptoms of pregnancy.
Urine tests can be performed either at home or in the clinic. There are several different types of home kits for testing urine available and by and large most of them have an accuracy rating of 97%. The method of testing varies and it is important to follow the instructions on the testing kit carefully. Some tests require you to immerse the apparatus in a sample of the urine while others require you to hold the apparatus under the flow. Most doctors recommend that you take a urine pregnancy test at home on the first day of your missed period. This is usually 2 weeks after conception and allows for the buildup of hCG hormone to detectable levels. Testing earlier may generate a negative response so remember, it is easier to wait.
If you get a negative result and are still experiencing some of the symptoms of pregnancy, then it is suggested that you wait a week before repeating the test. Alternatively, you can ask your doctor to take a blood test which has the advantage of being able to detect pregnancy earlier than a urine test.
Blood tests for pregnancy are of two types. Quantitative blood tests measure the precise amount of hCG hormone in your blood while qualitative blood tests detect only the presence of hCG in your blood.
They have the advantage of being able to detect a pregnancy at approximately 3 to 10 days from conception, earlier than urine pregnancy tests. Quantitative blood tests also have an advantage of providing your doctor with details about your hCG levels-important data if you are having problems in your pregnancy.
Blood tests may also need to be repeated at a later date if they give a negative result. Their disadvantage is that they are more expensive than a urine test and need to be done in a laboratory. The waiting period for the test results is also longer than a urine test.
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