How Accurate Are Home Pregnancy Tests?
Thinking you might be pregnant can be a terrifying prospect for some people and an utterly incredible one for others, but however you feel about it, it’s important to be able to take a reliable pregnancy test to know for sure. Unfortunately, some of the symptoms of pregnancy are the same as those women experience before menstruating, so you can’t rely on symptoms alone to confirm pregnancy, and doctor’s appointments are hard to come by in the UK and can take too long for some women to wait.
That’s where home pregnancy tests come in.
Home pregnancy tests are simple, affordable and easy to get hold of, but are they worth it? Here’s everything you need to know.
How Home Pregnancy Tests Work
Pregnancy tests work by checking the levels of Human Chorionic Gonadotropin (hCG) in the blood or urine to determine a pregnancy. When a woman is pregnant, her hCG levels will rise steadily for the first 10-12 weeks of pregnancy after the placenta has formed around 7-10 days after conception. Men and women have low levels of hCG in their blood normally, however, when pregnant, a woman will have significantly more hCG than normal, usually above 25 mIU/mL.
Urine pregnancy tests are small plastic sticks with an area for the sample to be collected and can be taken by urinating over the sample collecting area and waiting for the time period designated by the particular test. After the time is over, a positive result will be shown by two lines appearing on the test, the control line and the test line, and a negative result is shown by one line - the control line.
Some tests will have a cross rather than two lines to show it’s positive, and others will show a digital result, but this will be made clear in the packaging of your particular test. If the control line doesn’t show, then the test results are inconclusive and you should take another test to be sure of your result.
Some blood pregnancy tests will show results in a similar way, although they are taken by a finger-prick test that draws a blood sample to be dripped into the test rather than urinated on, however, most blood tests for pregnancy need to be sent off to a medical laboratory for accurate results and so can take up to 3 days for a result.
How Accurate Are Home Pregnancy Tests?
Both urine and blood tests for pregnancy are 99% accurate, however, there is more room for error with a urine test than a blood test due to the method of collecting and testing the sample. Blood pregnancy tests can detect lower levels of hCG than pregnancy tests that test urine, so they can be taken 10-14 days after ovulation (or around the expected start date of a period) and provide accurate results. Urine pregnancy tests, however, are recommended to be taken no sooner than one week after your expected period to ensure more accurate results.
Both urine and blood pregnancy tests can give false-negative and false-positive results, so if you’re going to take a pregnancy test at home, you should make sure you’re following the instructions and best practices to ensure the most accurate results.
How to Avoid False Pregnancy Test Results
It’s possible to take a pregnancy test and have a positive result that turns out to be false or a negative result that is incorrect, and both can be equally challenging emotionally if you’re trying or trying not to get pregnant.
For Urine Pregnancy Tests
With urine tests, you should also use your first urine of the day as your sample, as it won’t be diluted with liquid, so will have a higher concentration of hCG if you are pregnant and give a more accurate result. You should also be careful to wait for the given time after taking the pregnancy test, as checking the results too soon or too late may give an incorrect result. These are some of the reasons why urine tests can be less accurate than blood tests for confirming pregnancy, however, there are some factors that can affect the accuracy of any pregnancy test.
For Urine and Blood Pregnancy Tests
One of the most important things to remember when taking an at-home pregnancy test is that tests can expire, so make sure yours is in-date before you take it. It’s also relatively common for women to take a pregnancy test too early in their cycle and get a negative test, when, in fact, their placenta is still developing and hasn’t yet produced sufficient hCG to show up on the test.
It can be difficult to time your pregnancy test post-ovulation if you have irregular periods and menstrual cycles. Although, you can try to track ovulation symptoms, and make sure you take your test at least 10 days after your suspected ovulation date, or one week after your expected period if you’re taking a urine test.
As hCG levels rise throughout the first phases of pregnancy, they remain higher than normal through the remainder of the pregnancy and can be identifiable in the blood and urine up to 6 weeks after the pregnancy. So, if a woman has recently had a miscarriage or an abortion, her hCG levels will remain high and a pregnancy test may give false-positive results.
Moreover, some medicines can sometimes cause pregnancy tests to give false results, including:
- Fertility medication
- Antihistamines (anti-allergy medicine)
- Anti-anxiety medication
- Medication for seizures
- Medication for Parkinson’s Disease
If you’re taking any of these medications and are trying to get pregnant or simply want to know if you are pregnant or not, you should visit your doctor for advice on what test to take and when according to your personal circumstances.
It can be nerve-racking when your period is late, especially if you’re not trying to conceive, so it’s normal to want to have immediate results on whether you’re pregnant or not. But the sooner you take the pregnancy test, the less accurate it will be as the placenta needs at least one week to develop and start producing more hCG for the growing baby.
Blood tests for pregnancy should therefore be taken at least 10 days after ovulation as this is the only time during a menstrual cycle that women can become pregnant. If you don’t have regular cycles, you’re not alone. Women with irregular periods can benefit from using period-tracking apps and monitoring their ovulation symptoms to have an idea of when they’re in their ovulatory phase and likely to become pregnant.
Symptoms of ovulation include:
- Clear and egg white-like vaginal discharge
- Increased sex drive
- Tender or sensitive breasts and nipples
- Rise in basal body temperature (BBT)
- Pelvic pain
Not every woman will experience these symptoms, and some won’t have any at all, however, they are a good indication of ovulation and thus also fertility. If you’re not sure when you ovulate and are keen to know if you’re pregnant, you should take a pregnancy test around a week after you expect to have your period instead.
What to Do with Your Results
When you take a home blood test for pregnancy from Official Rapid Tests, you’ll get your results securely emailed back to you within 2 working days. If you’re pregnant, you should visit your doctor as soon as possible for an ultrasound scan to determine how far along in your pregnancy you are and how you would like to move forward. If your results are negative, you can try to conceive again during your next ovulatory phase. However, if you suspect you or your partner is infertile, you should visit your doctor for advice on your options.