Test 101

Pregnancy Test

When an individual thinks they are pregnant, there are two ways to take a pregnancy test. You can pick up a Home Pregnancy Test (HPT) or you can see a health care provider for a blood draw and pelvic exam. Typically, those who think they’re pregnant or are trying to become pregnant, do both.

The way a pregnancy test works is simply chemistry. When a woman is pregnant, her body is producing human chorionic gonadotropin, or hCG. This is simply a hormone that is present in a woman when she is pregnant. A pregnancy test will detect this hormone whether done at home or in a doctor’s office.

The difference between a pregnancy test administered by a health care provider and a HPT is just method by which the hormone hCG is detected. A home pregnancy test is designed to detect the hormone in urine and a health care provider will test blood for the hormone.

A home pregnancy test that has not reached its expiration date and that is performed according to the manufacturer’s instructions will be about 97% to 99% accurate. If you administer a HPT under these circumstances and it indicates you are pregnant, you should then schedule an appointment with an obstetrician. They will confirm the test results with a blood test in most cases and may perform a pelvic exam. It is important to continue to receive routine medical care throughout pregnancy.

There are few cases in which a home pregnancy test will register a false positive (indicating you are pregnant when you’re not). However, the most common reason for a false positive is if you are taking a fertility drug containing hCG, in which case you will already be under the care of a physician and will be monitoring your cycle.

A home pregnancy test can detect hCG at about 2 weeks and a blood test can detect it as early as 6 to 8 days. Most HPTs instruct you to repeat the test after 5 to 7 days regardless of the initial results and if you have missed a period. If your initial results are negative, but you’ve missed a period, repeat the HPT. If your initial results were positive, schedule an examine with an obstetrician.

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