If you suspect you may be pregnant, you'll likely want to know when to take a pregnancy test.
Firstly, it's important to understand how a pregnancy test works, so you can get the most accurate result from the test.
From the very beginning of your pregnancy, the fetus produces a hormone called hCG, or, human Chorionic Gondotrophin.
This hormone can be detected in your urine if you are pregnant. The levels of hCG increase as your pregnancy progresses, peaking at around 8-11 weeks, before dropping to a lower level at 12 and 16 weeks.
Some pregnancy test kits can detect hCG levels as low as 10 or 25mIU/ml. If you're pregnant, at 10 days past ovulation (DPO) you may be able to detect around 25mIU. At 12 days past ovulation, you should be able to detect around 50mIU and at 14 days past ovulation, 100mIU.
Are Pregnancy Tests Accurate?
Many home pregnancy tests claim to be over 99% accurate when taken on the first day of the missed period or earlier. However a study found that some pregnancy tests have poorer detection limits for H-hCG (which is what is found in early pregnancy urine) than others. It's more likely you will get a false negative than a false positive, due to a faulty test or having hormone levels too low to be detected.
When To Take A Pregnancy Test
So, when to take a pregnancy test? As mentioned above, pregnancy test kits are designed to detect levels of hCG produced by your body if you are pregnant. Your body may be producing hCG before your period is due, however it's ideal to test on the first day of your missed period.
If you test earlier than the first day of your missed period, you may indeed receive a positive result. But it's also more likely that you may end up with an inaccurate result. The test may come up negative if your hCG levels are not yet high enough to detect the pregnancy. On the other hand, it may show a positive result and not develop into a true pregnancy, due to the incidence of spontaneous miscarriage. These can occur before your period is due, and normally you would be none the wiser.
Is It True That It’s Best To Test In The Morning?
The pregnancy hormone hCG is usually at it’s highest levels early in the morning, so especially if you are early in your pregnancy, this is when it is the best time to test. It is important to note that excessive fluid intake before taking the pregnancy test can actually dilute hCG and this can make the result hard to read.
It’s always best to follow the manufacturer’s instructions included with the test, as the procedure can vary and affect your result if not done properly.
As soon as you have taken the test out of the packet, avoid touching the absorbent pad. There are normally two ways you can perform the test, midstream or in a cup. If you prefer to test midstream, all you need to do is hold the test almost vertically and pass it through a weak stream of urine, making sure you avoid water or urine being splashed on the device before starting the test.
If you prefer to use the cup method, urinate into a clean, dry container and dip the absorbent pad into the urine for 3-5 seconds. You do not completely immerse the absorbent pad, 1cm is sufficient.
I Am Taking Medication; Will This Have Any Affect On The Results?
If you are taking antibiotics, the contraceptive pill, or painkillers, this should not affect the result of the test. If you are on any fertility medication which contain hCG, you may receive a false positive. Speak to your pharmacist or carer for more info. Clomid does not produce false positives for pregnancy tests, but it can on ovulation tests.
What Does a Positive Pregnancy Test Look Like?
A positive pregnancy test will show a control line that was present before you took the test (usually quite dark) and a second line will appear after the urine passes through the window. Some tests now have two individual windows where lines need to show in each window. Other tests are designed to have a cross to show a pregnant test, so they can vary – just read the packet to find out what to look for.
The positive result line does not have to be as dark as the control line, but if you have a second line appear during the time frame specified on the packet – no matter how dark or faint – then congratulations – you are pregnant!
What Does a Negative Pregnancy Test Look Like?
A negative pregnancy test will only display the original control line; nothing else will show up at all after the urine has passed through the window. Sometimes you can have a very faint line come up after the designated time frame specified on the packet – it will tell you to wait a certain amount of minutes to show a result. After this time, the test should be discarded.
If The Test Result Is Faint or Hard to Read, Does That Mean I Am Not Pregnant?
It’s normal for the result on the pregnancy test to be either fainter or darker than the control line. The reason it may be fainter could be due to less hCG in your urine, especially very early in your pregnancy. It may be darker if your pregnancy is more progressed. Occasionally the test may display a ‘shadow’ line when the positive result should be, disregard this if you cannot see it when holding the test at arms length away from you and test the next morning.
How Long Should The Test Take to Work?
The test result should be read from 5 minutes and no later than 10 minutes. If any lines do appear after 10 minutes, it is still a negative result and must be disregarded. If you read the test sooner than 5 minutes, it may also be inaccurate as it has not had enough time to work.
What If There Are No Lines Visible At All On The Pregnancy Test?
It is unlikely that this will happen, but if it does, disregard the test. It may be faulty or due to not enough urine on the absorbent pad, too much urine on the absorbent pad or the test was not held correctly in the stream of urine. Repeat the test, carefully following the instructions as in the above question on how to use the test.
Should I Repeat The Test and If So, When?
If the result of your test was negative and your period still hasn’t started after a few days, test again. You may have miscalculated your cycle dates and / or the hCG level may be too low to detect. If you still receive a negative result after the second test and still have no period, consult your doctor. Some women find that they do not get a positive result as soon as others and some have only been able to detect pregnancy with a blood test. Everyone is different; however if you are concerned, do see your doctor.
What Should I Do If I Am Pregnant?
You should start considering options for pre-natal care, be it a midwife, Obstetrician, GP or combined care if you haven’t already. If you wish to see an Obstetrician you will need a referral from your GP. Many midwives, birth centres and Obstetricians do book out very quickly these days so be sure to make researching your options a priority. BellyBelly has some articles to help, Who Cares? Choosing a Model of Maternity Care, and Public, Private, Birth Centre or Home?.
What Can I Do If I Am Trying To Get Pregnant But Haven’t Been Able To?
It is normal for a couple to conceive anytime in the first twelve months of trying. You can try charting your cycle or using ovulation prediction kits (OPK's), which work in the same way as pregnancy test kits – by measuring hormone in your urine. They can help you to identify your most fertile period by detecting luteinizing hormone, which signals likely ovulation in the next 24-36 hours.
The BellyBelly Forums also offer great support for those trying to conceive over short and long periods of time, including assisted conception.
Where Can I Get More Help and Support?
BellyBelly has a section in the Forums dedicated to home pregnancy tests and ovulation prediction kits. You can read others questions or post your own in our pregnancy test discussion forum. Alternately you can call the advice line numbers found on most pregnancy test kit packets or their information leaflets.