How do hpt work

Some can even indicate how far along the pregnancy is. Various pregnancy tests are available for purchase online. A person may opt for this to avoid some of the handling errors that can happen with home tests.

Otherwise, the level of accuracy is the same as with home testing. Waiting times for clinical results vary. Some facilities provide results immediately, while others may take up to a week.

These are less common than urine tests, but they can give results earlier in a pregnancy. There are two types. A qualitative hCG blood test checks whether the hormone is present in a blood sample.

Anyone who can become pregnant and suspects that they are should take a test. This might be an especially good idea for people who have recently had sex without a barrier method of protection, such as a condom. Learn more about the early signs of pregnancy here. Depending on the test, this involves giving either a urine or blood sample. Healthcare professionals may test this immediately or send it to a laboratory for testing.

The lab usually takes a day or two to return the results. Home pregnancy tests are simple to use, but it is crucial to follow the instructions carefully. In general, they involve:. It is often best to take a pregnancy test 1—2 weeks after the first missed period. A person may want to wait a bit and test again if they suspect pregnancy but receive a negative result at first.

A positive result is typically correct. A negative result is more likely to be incorrect. Most tests can produce accurate results on the first day after a missed period, but to ensure accuracy, it is advisable to start testing 1 week after a missed period. This might result from a person having irregular periods or miscalculating when their period was due. A positive result typically indicates pregnancy, while a negative result tends to mean that the person is not pregnant.

It is more likely for a negative result to be incorrect. It is important for anyone using a home test to follow the instructions carefully and understand what each color change or symbol indicates.

A positive result indicates pregnancy. This is true even if the color change, word, or symbol on a home test is faint. Implantation usually happens a week or so after ovulation. It can take several days for HCG levels to rise high enough for a test to detect the hormone. Due to how long it takes for HCG levels to rise, it is possible for a woman to be pregnant and still get a negative test.

A positive result usually appears after retesting a few days later. False-positive results are rare. However, because home pregnancy tests are increasingly sensitive, some can detect very early pregnancies with low HCG levels. This sensitivity means it is possible to have a positive test that a very early miscarriage then follows.

A woman who delayed testing or who used a less sensitive test might not have known about the miscarriage. In rare cases , a woman can have abnormally high levels of HCG even though they are not pregnant. The most common reasons for this include:. In addition to testing too early, the following factors can cause a false negative with a urine HCG test:.

Tests that have passed their expiry date may produce false positives or negatives. Reused tests are not accurate. HCG tests are very safe. The urine test is risk-free. The blood test can cause brief pain and occasional bruising at the puncture site. Urine HCG tests often return false-negative results, particularly very early in pregnancy.

This can be stressful and demoralizing to people struggling to become pregnant. Blood tests are typically more accurate, though even these may fail to pick up low levels of HCG in early pregnancy. It is also possible to get an early positive result. Some women get positive tests very early in pregnancy and then have a miscarriage a few days later. If they had not had an early HCG test, they might not have known they were pregnant. This can be a stressful and alarming experience, with some people experiencing intense grief over the lost pregnancy.

Most people first learn about a pregnancy through a home HCG pregnancy test, and many confirm that the pregnancy is healthy with blood HCG testing. Though imperfect, the test is typically reliable, particularly as a pregnancy progresses. The information that a single HCG test provides cannot differentiate between ectopic pregnancies, molar pregnancies, or other pregnancy complications.

Although abnormally high or low HCG levels can indicate a problem with the pregnancy, this is not always the case. People who have concerns about the development of the embryo or the pregnancy should ask a healthcare provider about additional testing options. Examples include:. If any line, symbol, or sign shows up in the results window, no matter how faint, you can consider the home pregnancy test result to be positive. A line will not show up if the test does not detect hCG—so even the faintest line means that the test has picked up on hCG in your pee.

If you got a positive test result on your home pregnancy test, it is important that you make a medical appointment. Your doctor can confirm the result of your home pregnancy test and begin prenatal care. Your test result is only accurate if you see the indicator during the specified amount of time. If the instructions say to wait three minutes, whatever shows in the result window after three minutes is your test result.

If the test sits for too long, an evaporation line may appear. If any line, symbol, or sign shows up after the amount of time specified in the instructions, this is not considered a positive pregnancy test result.

If the home pregnancy test gives you a negative result, but you do not get your period, you should retest in 3 to 5 days. If you ovulated later in your cycle or did not properly calculate your ovulation date, you may have taken the pregnancy test too soon to receive a positive test result.

Since the amount of hCG increases rapidly when you are pregnant, you may end up with a positive test just a few days after a negative one. This is why some home pregnancy test kits come with more than one test—so you have another one to re-test with. If you took your test fewer than 7 days after your missed period, do not automatically believe that a negative test result means that you are not pregnant. You may have taken the home pregnancy test too soon. Wait another week.

If by that time you still have not gotten your period and are still getting a negative test result, you should make an appointment with your doctor to figure out if something may be going on.

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