Last reviewed by Editorial Team on August 27th, 2018.
How do pregnancy test works?
Home pregnancy test contains a ingredient (Y shaped proteins called antibodies), which detect hCG hormone. In an expired pregnancy test, the level of this ingredient / chemical gets depleted with time hence pregnancy test failed to detect hCG in the urine of the women and get expired over time. The average shelf life of a pregnancy test is 2 to 3 years.
When should I take a home pregnancy test?
Various home pregnancy tests claim to be best accurate as early as the first day of a missed period or even before. You’re likely to get more accurate results, however, if you wait one week after your missed period.
Shortly after an implantation of fertilized egg, the placenta forms and releases the hormone human chorionic gonadotropin (HCG). HCG enters your bloodstream at the beginning and urine after some time. During early pregnancy, this hormone concentration increases very fast doubling every 2 to 3 days. So, the earlier you take the home pregnancy test the harder it might for test to detect HCG.
Keep in mind that the precise timing of ovulation might be different among women or even from month to month, and the fertilized egg can implant in the uterus at different times. This can affect when HCG production begins and becomes detectable.
If it’s important to confirm your pregnancy right away, depending on how far along you are in your pregnancy, your health care provider might recommend that you have an ultrasound, repeat a urine test in the hospital or clinic lab, or have a blood test to measure your HCG.
How can I check my pregnancy at home?
In order to check your pregnancy safely and in a proper way at home follows next steps:
- Prepare yourself. Checking your pregnancy is always a nerve-wracking experience, especially when you’re anxiously hoping for positive or the other result. So, always take the test privately and give as much time as you need to yourself. Before start, wash your hands with soap and warm water, then carefully remove the testing stick, track or a tile from its cover.
- Carefully read the label how to properly use there are different types of test, however they are mostly similar
- Do the test! Sit on the toilet and urinate either directly on the testing stick/track or into the small sterile plastic cup depending on the type of test. Try to make a midstream sample during urinating. The best way to do that is to pee a little first before you collect any urine in the cup or insert the stick. If you have to urinate directly on the track or stick, first make sure to read, understand and follow the instructions carefully. Some tests require urinating on the stick for a specific time, for example exactly 5 seconds and no more or no less. In that case use a stopwatch, if necessary. When urinating on the stick, place the absorbent stick end into the urine stream and turn it so that the display faces upwards.
- Some tests require dropper use. In these cases use the dropper and place a small amount of urine onto the test stick. This is only necessary for the tests with plastic cup method. Drop the urine into the well indicated on the test stick. Alternatively, some brands need that you put the absorbent end of the stick into the collected urine. Hold the test stick there for 5 to 10 seconds, or for the amount of time written on the label.
- Wait some time as stated on the instruction label. Place the stick on a sterile, clean surface with the end result window facing up. Wait time is usually between 1 to 5 minutes, however there are some tests that may take up to 10 minutes to give an accurate result. Try not to watch at the stick during this waiting period, since you will become even more anxious, so do something to distract yourself. Some sticks are advanced and may have a little timer symbol or line to show that the test is working. If nothing appears on the screen, it is very likely that your test is not working correctly and you may need to use a different one.
- Check the results. Once the stated amount of time has passed, check the test for results. The symbols that are usually used to indicate whether you are pregnant or not may vary from test to test, so read the instructions carefully again in order to be sure. Most home pregnancy tests use plus or minus symbolling, or a coded color change, or even the words “pregnant” or “not pregnant” on a digital display. Rarely a line or symbol may appear very faintly on the display screen. If this happens, you should consider it as a positive result as this indicates that hCG hormone has been picked up in your urine. False-positives are very uncommon. If the results of pregnancy test are positive then you should make an appointment with your healthcare provider to confirm your pregnancy. Confirmation is usually done using a blood test. If the result of home pregnancy tests is negative wait another week and if you still haven’t started your period you should do the test again. False negative tests are very uncommon, but it can happen especially if you done wrong calculation of your ovulation time and took the test too soon. This is why many home pregnancy tests should come with two test sticks.
How accurate are pregnancy tests?
If it is positive, statistically the test is probably right. That is because home pregnancy tests measure hCG- human chorionic gonadotropin hormone that gets maximal concentrations in the urine about 6 to 12 days after conception. If you are not pregnant, then you won’t have any hCG in your body.
However, if the test was negative, there is a chance that you could still be pregnant. The biggest factor that could have an impact on your test result is the time when you took the test, since it is more probable to pick up the hCG hormone in your urine the longer you wait to take it.
So, it is right that some tests claim to be 99 % accurate on the day you miss your period, but that’s perhaps not true. You are most likely to get most precise result if you wait until about a week after you were supposed to start your period.
Do pregnancy test expire?
Yes, pregnancy tests do get expired over a period of time. Just like all other products in the market, pregnancy tests also comes with a designated expiry date. The pregnancy test contains a chemical, which detects the hCG hormone in the women’s urine and when this chemical becomes unable to detect the hCG in urine, the pregnancy tests gets expired.
The chemical, changes its colour, when it comes in contact with hCG, can lose its activity after a specific period of time. Thus it is always important to check the expiry date on the box or outer package of pregnancy test. Using a expired pregnancy test can give a false result, therefore a near expiry or expired pregnancy test should be thrashed.
Expired Pregnancy Test
When home pregnancy tests lose their shelf life (that is the time for which tests remain usable), or when home pregnancy tests can no longer of use, they are called expired pregnancy tests.
Many women are unaware of the fact that home pregnancy tests can also get expired. To ensure the most accurate and proper result of your pregnancy test, you must be aware of using right product.
HCG (Human chorionic gonadotropin hormone) is the hormone that is detected when a fertilised egg implants into the uterus, this hormone is involved in implantation process. In early stages of pregnancy, HCG levels rises and doubles every 24 hours and reaches to maximum within 8 to 10 weeks.
When Do Pregnancy Test Expired?
All pregnancy tests are produced with a shelf life of 2 to 3 years. All pregnancy tests are meant to detect the hCG in human body. Branded pregnancy tests are considered as more reliable as compared to generic ones. Based on the price, expensive pregnancy tests provide longer shelf life as compared to cheaper ones.
Different brands have different shelf lives for different pregnancy tests. Usually all manufactures print an expiration date on outer packaging or box of pregnancy test. To get the accurate results, you should buy the pregnancy test, at the time you want to use it.
Why Do pregnancy test expired?
So many women left wondering, why pregnancy tests gets expired? The reason behind expiry of pregnancy test is inability to detect the hCG in urine. Once the chemical looses its ability to check the hCG in urine, than it will not be able to work properly.
The expiry date is always mentioned on the box or the outer packaging of the pregnancy tests, that includes a month and a year. For example : Jan 2018 which left many women wondering that the test will expire on first day or last day of the month January.
In such cases, 1st day of the January, the pregnancy test should be considered as expired. Thus after getting proper information about expiry date of the pregnancy test, a new and more reliable product should be used.
Are expired pregnancy tests accurate?
Almost all pregnancy tests that are available in the market purports to be 99% accurate but they are of no use once they get expired. An expired pregnancy test may work sometimes but the results can not be considered as reliable and accurate.
The chemical, that is used to detect the hCG in pregnancy tests became inactive past its expiry date, which may give you inaccurate results. So, One should not bother using an expired pregnancy test, in order to avoid difficulties in confirming your pregnancy.
What happens when you use an expired pregnancy test?
Usage of expired pregnancy test may result into:
- Inconsistent and disappointing results.
- False negative reading due to its inability to detect hCG in urine.
- False positive readings, which are quite common also.
- If exposed to heat or moisture, expired pregnancy tests can produce false positive readings.
How to choose right Pregnancy test?
When you are pregnant and seeking for the best product to confirm it, You can not afford to get the wrong pregnancy test. There are few tips that will help you to choose the right pregnancy test:
- It should be easy to use and easy to read.
- It should give you 99% accurate results.
- Digital tests are more accurate and reliable.
- Always check the Expiry date on the box or the outer package of pregnancy test.
- Choose branded pregnancy test over generic one in order to avoid wrong results.
- Always buy the pregnancy test at the time you want to use it.
Home pregnancy tests are the tests / kits that are used to detect hCG (human chorionic gonadotropin) in women’s urine and confirm the pregnancy. These tests are comes with an expiry date, which is one of the most important factor when it comes to selecting a reliable pregnancy test. An expired pregnancy test not only results in the inaccurate findings but also disappoints you with false readings.
Price, accuracy and sensitivity levels are other important factors to consider when you shop for a pregnancy test. If you are unsure about expiry date of the pregnancy test, you should talk to the seller regarding this. You should not buy an expired or a near expiry pregnancy test in any condition. As now a days pregnancy tests are available for as little as $1, you should use a pregnancy test that is reliable for something as important as pregnancy.