What Happens When I Take a Pregnancy Test?

If you have been trying to conceive or ever had a pregnancy scare while actively avoiding conception, then you may be intimately familiar with the at-home pregnancy test. These expensive little sticks can quickly become addictive, as we pee and pee again to find out what our future holds.  But do you know how they work? 

These at-home tests chemically screen your pee for the human chorionic gonadotropin hormone (HCG). Seven days after fertilization, your growing embryo begins to produce this hormone in order to send a chemical signal to the ovaries to produce progesterone and estrogen. These hormones in turn keep the lining of your uterus nice and thick, so the embryo can have plenty of nutrition as it grows. 

At-home urine tests can sense elevated HCG levels within 14 days of conception. That being said, blood tests at the doctor’s office are  even more reliable. If these tests find that you have more than 25 units of HCG in your blood, that means you’re pregnant!

During the first month of pregnancy, your embryo is growing so fast that HCG levels in your body double every two days. By testing to make sure your HCG levels are increasing in the early stages of your pregnancy, you and your doctor can make sure that your embryo is developing as it should.

Be aware though that HPTs are not full-proof. You can get false-negative and false-positive results. What does that mean exactly? 

FALSE NEGATIVE

A false negative result is one where the test says you are not pregnant, but in fact you are. This can happen if:

+ You take the test too early. The earlier after a missed period that you take a home pregnancy test, the harder it is for the test to detect HCG. 

+ You check test results too soon. Always be sure to use the test in the way directed by the manufacturer.

+ You use diluted urine. For the most accurate results, you should take the test first thing in the morning — when your urine is the most concentrated.

FALSE POSITIVE

A false positive result is one where the test tells you you are pregnant, when in fact you are not. This can happen if:

+ Blood or protein is in your urine.

+ You take certain drugs such as tranquilizers, anticonvulsants, or hypnotics, and some fertility drugs, may also cause false-positive results.