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Pregnancy Test Kit Accuracy and Sensitivity
Know the Facts & Learn the Tips to Get Early, Accurate Results!

Whether it's the first time or the thousandth time, using a home pregnancy test can be an emotional roller coaster. If you have been trying to conceive for a while, waiting for that first big fat positive can be a bit 'trying' indeed, and sometimes downright frustrating. And then there are the nagging questions: It it too early to test? When can I take a pregnancy test? Is that a faint line I see or is it my hopeful imagination? What can interfere or affect a test result? And how do these pregnancy tests work anyway!?!

How does a home pregnancy test tell you if you are pregnant?

To understand how the home pregnancy test works, visit our instructions page. The first tip in pregnancy testing is to follow the instructions closely - and to understand the principles behind the diagnostic science. FDA-Approved HPTs are over 99% accurate in laboratory settings (which means that if you follow instructions and observe the testing tips, your results will be accurate!). To provide a brief summary, a pregnancy test 'reacts' to a special pregnancy hormone called hCG that is produced by the developing embryo and is found in a woman's urine. On average, at around seven-to-ten days past ovulation, there should be enough hCG hormone in a pregnant woman's first morning urine to start producing positive lines on high-sensitivity pregnancy tests like ours.

However, please note that hCG increases in your system at different rates among different women. Whether a positive or negative result, we recommend that you repeat a test to confirm the result in a few days. A negative result early on does not foreclose the possibility of pregnancy, so test again using a first morning urine sample. And once again, do read the instructions (every word) closely to ensure that you are using and interpreting the test correctly.

Blood Pregnancy Tests vs. Urine Pregnancy Tests: Which are better?

While home pregnancy tests are designed only for urine samples, there are also blood pregnancy tests which can be taken at a clinic or your doctor's office. Both blood and urine pregnancy tests detect the hCG hormone, they just use a different bodily fluid to achieve the same end. A blood test is, typically, more sensitive than a urine test, and with a quantitative test you can actually learn the exact amount of hCG hormone in a blood sample. In the old days (like a decade or so ago), home pregnancy tests were very expensive and complicated, often requiring quasi-laboratory-like procedures! Today, as you know from reading our website at Early Pregnancy Tests.com, home testing is quite simple and very affordable. If you do receive a positive on a home test, it is still recommended to contact your doctor right away for a follow up test and to learn important facts to ensure a healthy pregnancy for both you and your baby.

As noted above, there are two types of doctor-administered blood tests: quantitative and qualitative. A quantitative test (beta hCG) is highly accurate because it measures the volume of hormone - providing you with a number that reflects the amount in your system. Like home urine kits, a qualitative hCG blood test simply determines if hCG has reached a specific gravity or "positive threshold". A urine test (hpt) and the qualitative blood hCG test both function like a light switch (it's either on or off) giving you a "yes" or "no" answer to the big question..

Common Questions about Testing Accuracy

How accurate are home pregnancy tests? As indicated above, pregnancy tests are very accurate - over 99% accurate when used properly. Before using a test, ensure that expiration date has not passed. Our tests at Early Pregnancy Tests.com offer the maximum allowable 2-year expiration dates.

When do I start Testing? Start dates depend on specific test sensitivity. With our tests, you can begin testing at around 7-10 days past ovulation. Note that the quantity of pregnancy hormone increases nearly exponentially each day in early pregnancy just following implantation. Use a first morning urine sample to increase testing accuracy. In early pregnancy, your test line might be faint. As hCG increases, your faint positive should slowly transform into a big fat positive.

What are the variables that impact accuracy (or early detection)? Actually, there are many - and each variable corresponds to a specific testing tip to help ensure that your result is as accurate as possible.

- Implantation Date: Implantation can take place soon after ovulation - or up to a week or so. This means that the hCG hormone can start flowing early, or it may be somewhat tardy. The date of implantation is a key variable, because hCG will not be present in your system until the embryo implants in the womb. Tip: Chart fertility to learn when you ovulate. Not every woman has a 28 day cycle. And not every cycle is going to be the same length. By BBT charting for ovulation you can know when you are most fertile - and you can also determine when you can begin testing for pregnancy.

- Rate of hCG Increase: Following implantation, hCG will be produced, though at variable rates among women. In most cases, it increases very rapidly, doubling nearly every day. The amount of hCG in urine will be at its highest concentration in first morning urine samples. Tip: Use first morning urine! If you can't - or don't have time - and you need to test later in the day, hold your urine for as long as possible before collecting a sample (and avoid drinking a lot of fluids before testing that might). Avoid caffeinated beverages before testing as they will act as a diuretic. If you receive a negative result early on, wait a few days and test again....

- Sensitivity of Test: Different tests have different sensitivity thresholds. The more sensitive the test, the sooner you can test. Many drugstore brands require that you wait until your missed period to test. But this, in a way, sort of defeats the point... With a high sensitivity, early detection pregnancy test, you can learn if your are pregnant before your missed period. Tip: Use our FDA-Approved pregnancy tests which have the highest sensitivity levels and full two-year expiry dates.

- Fertility Drugs: There is not much that interferes with a pregnancy test kit, so that's good news. Most prescription and OTC drugs do not affect test results, nor will birth control pills. However, some fertility drugs do contain hCG and can cause a false positive pregnancy test. Clomid, among the most popular ovulation-induction fertility medications, does not contain hCG, so no worries there. Tip: If you are taking fertility medications, ask your doctor if or how they will interfere with using a home pregnancy test (or an ovulation test, for that matter, as clomid can cause some problems with OPKs). Happy testing!

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