A home pregnancy test is a convenient and affordable way to quickly find out about pregnancy. Modern tests are quite accurate, but sometimes they give erroneous results. Most often, the reason for this is inattentive reading of the instructions. We tell you how and when to take a pregnancy test to get an accurate result.
How does a pregnancy test work?
When fertilization occurs and the egg is implanted into the uterine wall, women begin to produce a special hormone – human chorionic gonadotropin. For short, it is called hCG. This hormone is only found in pregnant women. If it is detected in the blood or urine, it can be concluded that the woman is expecting a child.
Home pregnancy tests use a special reagent that is sensitive to hCG. If the urine contains the necessary hormone, the test will show a positive result. If there is no hCG, the test will be negative.
When can I do a pregnancy test?
Since the amount of hCG increases gradually, it is recommended to take a pregnancy test no earlier than the first day of a missed period. If the cycle is regular, 10 to 14 days should have passed since conception by this time. During this time, enough hormone accumulates in the urine for a home pregnancy test to detect it. The second way is to count 21 days from the moment of unprotected sex.
It’s more difficult to determine the right date for testing if your cycle is irregular . In this case, count 36 days from the first day of your last period or four weeks from unprotected sex.
If you need to find out about pregnancy earlier, you can give blood for the hormone hCG. The analysis will show pregnancy already 10 days after conception. But keep in mind that conception does not always occur on the day of unprotected sex, since sperm can live in a woman’s body for up to five days and wait for the egg to mature.
Which test to choose?
The tests differ in their sensitivity to the hCG hormone, which is indicated on the packaging. For most tests, it is 20–25 mIU/ml. This is usually enough to find out about conception from the first day of the delay. Some tests have a sensitivity of 10 mIU/ml and promise to determine pregnancy as early as 6 days before the delay. However, they are more expensive, and the accuracy of the result also depends on the regularity of the woman’s cycle.
The next thing to look at is ease of use. There are three types of pregnancy tests:
— Test strips. You need to pee into a clean container, and then dip the sensitive part of the test strip into the urine.
— Tablet tests. You need to pee into a clean container, and then use a pipette to drop a few drops of urine onto the test.
— Stream tests. You need to place the tip of the test under the urine stream.
How to take a pregnancy test correctly?
Before taking a pregnancy test, read the instructions carefully: they may differ from manufacturer to manufacturer. Pay attention to how the test shows the result. On some tests, two stripes appear in case of pregnancy, on others, a plus sign or the inscription Pregnant.
Usually, manufacturers make a special marker that shows that the test is not damaged and works correctly. For example, if one strip appears, the test worked, there is no pregnancy. Two stripes – there is pregnancy. No stripes – the test did not work. In the latter case, you need to buy a new kit and take the test again.
Make sure you dip the sensitive strip into the urine no higher than the indicated mark or drip into the correct part of the sensor. Usually, you need to wait a few minutes for the results to appear. Set a timer to keep track of the time accurately.
Is it possible to take a pregnancy test in the evening?
Usually, the instructions for pregnancy tests recommend using morning urine. The fact is that it is concentrated and the hCG level will be the highest for the day. Therefore, you have a lower chance of getting a false negative result. However, if your period is already a week late or you have chosen a test with a sensitivity of 10 mIU/ml, you can take it at any time of the day. Try to make sure that at least three hours have passed since your last visit to the toilet and do not drink too much liquid.
Can I take a pregnancy test if I am taking oral contraceptives?
If you are using oral contraceptives and suspect pregnancy, you can take the test. The pills do not affect the results because they do not contain hCG.
The only medications that can interfere with home pregnancy tests are certain fertility drugs that contain hCG. If you are taking these, your doctor can help you determine if you are pregnant.
What if I can’t determine the test result for sure?
Sometimes the second strip is too pale and unclear. Most likely, this means that you are pregnant, but the hormone level is so low that the test barely sensed it. It would be a good idea to have your blood tested for the hCG hormone or to do a repeat home test in two days. During this time, the amount of hCG will increase , and the test results will be brighter.
Can the test result be wrong?
Modern pregnancy tests are 99% accurate , with false negatives being more common than false positives. You may get an incorrect test if:
– it is expired or spoiled;
– you did not follow the instructions;
– You took the test too early.
If you doubt the results, take a repeat test in two days.
What to do if the test is positive?
If the test is positive, contact your gynecologist as soon as possible. He or she will help make sure that the pregnancy is proceeding normally and will draw up a plan for its further management. If you are not planning a child, your doctor will help you choose the appropriate method of termination of pregnancy.
If several tests show a negative result, but menstruation does not occur, this is also a reason to contact a gynecologist. He will help to find out the reason for the delay and prescribe treatment, if necessary.