Pregnancy tests

A pregnancy test can tell you if you are pregnant. Here are answers to some common questions about them.

What is a pregnancy test and how does it work?

Pregnancy tests check your urine or blood for the presence of a hormone called human chorionic gonadotropin (hCG). The body produces this hormone after a fertilized egg attaches to the wall of the uterus.

This usually happens about 6 days after fertilization. hCG levels increase rapidly, doubling every 2-3 days.

What types of pregnancy tests are available?

The two main types of pregnancy tests are blood tests and urine tests.

Blood tests

You get them at the doctor's office, but they're not used as often as urine tests. These tests can detect pregnancy earlier than a home pregnancy test, about 6 to 8 days after ovulation. It takes longer to get results than with a home pregnancy test.

Two types of blood tests for pregnancy:

A qualitative hCG test simply checks for the presence of hCG. It gives a yes or no answer to the question "Are you pregnant?" Doctors often order these tests to confirm pregnancy as early as 10 days after conception. Some may detect hCG much earlier.
The quantitative hCG test (beta-hCG) measures the exact amount of hCG in the blood. It can find even very low levels of hCG. These tests can help track down problems during pregnancy. Your doctor may use these along with other tests to rule out an ectopic pregnancy, when a fertilized egg implants outside the uterus, or after a miscarriage, when hCG levels drop rapidly.

Urinalysis

You can take them at home or at your doctor's office.

Home pregnancy tests are not only confidential and convenient, but also easy to use. They are also very accurate if you follow the instructions. All of these pregnancy tests work in the same way. You test your urine in one of the following ways:

Keep the test strip in the urine stream.
Collect the urine in a cup and dip the test strip into it.
Collect the urine in a cup and use the dropper to pour it into another container.

You will have to wait a few minutes before seeing results.

After taking this test, you can confirm your results by talking to your doctor, who can perform even more sensitive pregnancy tests.

How accurate are pregnancy tests?

Home urine pregnancy tests are about 99% accurate. Blood tests are even more accurate.

The accuracy of a home test depends on:

How closely you follow the instructions
When you ovulate and how soon the egg implants
How soon after pregnancy you take the test
The sensitivity of the pregnancy test

When to take a pregnancy test

Some pregnancy tests can detect your hCG levels before you even stop having your period. But the results will be more accurate if you wait until the first day of missing your period.

The results may also be more accurate if you test in the morning when your urine is more concentrated.

Where can I get a home pregnancy test?

You can buy a home pregnancy test at a pharmacy without a prescription. The cost depends on the brand. But most tests are not very expensive.

What do pregnancy test results mean?

The results can be displayed as a line, a color, or a symbol such as a "+" or "-" sign. Digital tests show the words "pregnant" or "not pregnant." It is important to know what a positive or negative result means.

If you get a positive result, you are pregnant. This is true regardless of the clarity of the line, color or sign. If you get a positive result, you can call your doctor to discuss what to do next.

In very rare cases, you may have a false positive result. This means you are not pregnant, but the test says you are. You may have a false positive result if there is blood or protein in your urine. Some medications, such as tranquilizers, anticonvulsants, sleeping pills, and fertility drugs, can give false positive results.

If you get a negative result, you are probably not pregnant. But you can get pregnant if:

The test is past its expiration date.
You took the test the wrong way.
You tested too soon.
Your pee is too diluted because you drank a lot of fluids right before the test.
You’re taking certain medications, such as diuretics or antihistamines.

If you get a negative result, try testing again in about a week to double check. Some home pregnancy tests suggest doing this regardless of your first results.

If you test twice and get different results, call your doctor. A blood test is a good idea to confirm the results.

If you have any further questions about a pregnancy test or its results, call your doctor or the phone number provided with the test.