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Pregnancy tests are available from many different manufacturers, and the results displayed on these tests differ by the test utilized. As pregnancy tests have become so reliable, medical professionals consider these results accurate and do not require bloodwork unless another concern or problem exists. However, there are ways to ensure the result is as accurate as possible when performing a home pregnancy test.
During pregnancy, the body produces a hormone called human chorionic gonadotropin (hCG). This hormone begins production approximately ten days after conception, as this is when the fertilized egg implants in the uterus. Home pregnancy tests detect hCG in the urine and are very accurate when utilized appropriately. Pregnancy can be determined by either blood or urine, and home pregnancy tests use the body’s urine.
When the pregnancy test detects the hCG hormone, the paper in the test reacts with the hCG and causes the test to display a specific result, such as a line, a plus sign, or the word “pregnant.” The test will only detect exact amounts of hCG, so timing is important when utilizing a home test. With home pregnancy tests, there is typically more concern with false negatives (from testing too early) than false positives. The only medications that could cause a false positive are certain fertility medications. Otherwise, false positive results are rare unless the test is defective.
As indicated, it does take time for the body to produce hCG after the egg is fertilized. Therefore, it is crucial to understand that various tests react to certain hCG levels. Given that the body typically starts producing hCG approximately ten days after the egg is fertilized, it is usually recommended that tests be taken after the first missed period. While it is possible to see a positive result ten days after contraception occurs, waiting until after the first missed menstrual cycle reduces the chance of a false negative. A false negative can be seen if the pregnancy test is taken too soon and the body has not had enough time to produce enough hCG to be detectable by the urine pregnancy test.
In comparison, a blood test (which has to be ordered by a medical professional) can detect smaller amounts of hCG in the blood sample and may show a positive pregnancy within 9 to 14 days after contraception. Blood tests are only commonly performed if there has been a history of infertility or other issues or the health care provider wants to monitor how much hCG is being produced.
Taking a pregnancy test first thing in the morning increases the chances of an accurate result. Overnight, some hCG (if present) will build up in the urine, so using the first urine of the morning will ensure there is enough hCG to show positive. It is possible to use urine at any time of the day, but the first urine of the morning after waking up will contain the highest amount of hCG. This means that there is a more significant result of testing positive if one is indeed pregnant. This is especially important if you drink a lot of water throughout the day, as your urine will be more dilute, and it will be harder for the test to detect hCG.
Since many different types of pregnancy tests are available, one must read the directions before using them. This will also increase the chances of an accurate result, so no error occurs. Especially for those people who have taken pregnancy tests before, it is important to recognize that tests may be different. Every test has instructions that should be followed precisely for the correct result.
The test utilized will come with instructions and indicate how long to wait before reading the test. It is essential to check for the control line or indicator (this ensures that the test is working correctly) and only read it after the correct amount of time has elapsed. Some tests will show a result as quickly as a minute, while others may take 10 minutes. Reading the test too soon could be a false negative as if the amount of hCG is low, the line or result may be light and not show until the full time has passed. However, if a pregnancy test is read after too much time has gone by, it is possible to see an evaporation line which should not be mistaken for a positive result.
A pregnancy test can be held in the urine stream or dipped into a cup with the urine sample. Holding the test in the urine stream can be messy, and the urine may not hit the correct part of the test, leading to a false negative. Peeing in a cup may not seem as sanitary to some, but it could improve the accuracy as it is easier to see where to dip the test and to count how long the test is exposed to urine.
Just because a pregnancy test is purchased from the store doesn’t mean it is not past the expiration date. Stores can forget to check for outdates or even rotate their stock incorrectly. If tests are purchased in bulk, always check the expiration date, just in case. Using an expired test can render it ineffective, leading to an inaccurate result.
Positive and negative results vary according to the type of test utilized. Typically, one line is negative, and two lines are positive. This is because one line is the control line and shows the test is working correctly. Other tests may read “pregnant” or “not pregnant,” show a positive or negative sign, or different variations. It is essential to read the instructions to know what to look for, and it is important to note that the control line does not indicate a positive pregnancy.
If you are trying to become pregnant and keep getting negative results, depending on your age and other conditions, you may want to reach out to your doctor to see if there are options. With positive results, calling the doctor to schedule your first appointment should happen within a few days of a positive result. Most first appointments occur around week 8 of pregnancy, so calling right away to get on the schedule is important. If anything unexpected or of concern happens between the positive result and your appointment, one should contact their doctor for advice.
Anja Health is an excellent partner throughout your pregnancy journey. From informational articles, patient education, and the support of everyone on their path to parenthood, Anja Health is a trusted source to ensure your baby’s health is a top priority from pregnancy and beyond.