Can An Early Pregnancy Test Be Wrong?

Early Pregnancy Test Accuracy

Woman looking at pregnancy test.
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When you think you might be pregnant, you usually want to know as quickly as possible. As more and more pregnancy tests advertise that they can tell you, even before you miss your period, you might wonder if that's true. Many people wonder if they take an early pregnancy test too early can it be wrong? 

How a Pregnancy Test Works

A urine early pregnancy test works by measuring the amount of hCG (pregnancy hormone) in your urine.

Typically you need to have missed your period for these to be accurate, particularly a positive result. That said, if you have a positive a couple of days before this missed period, hCG has been detected and you are pregnant.

As the tests become more sensitive, more and more women will have positive results earlier. That leaves the problem of taking a pregnancy test prior to your missed period and getting a negative result.​

If you get a negative result and you have tested prior to your missed period, you will need to wait a couple of days and retest. You can usually skip this step if your period starts. However, if your period is light or short, you may consider taking a pregnancy test in case the bleeding you experience was really implantation bleeding.

Why You Need to Diagnose Pregnancy Early

The desire to figure out if you're pregnant is a strong one. So it makes sense that you would want to know as soon as possible if you were pregnant.

This can also help you get your pregnancy off to a great start by ensuring that you are doing what you can to be healthy. (Though in reality, you should be acting pregnant until you know otherwise, just in case. That saves a lot of worrying for moms down the road.) But our desire to know, the technology and the fluctuations in our bodies are so great, that it can be difficult to make a test that works for every single person.

Knowing that you are pregnant earlier, rather than later, also provides you with a number of benefits. It allows you more time to find a practitioner and begin your prenatal care. It also encourages you to begin or continue taking prenatal vitamins and reducing the risks in your life that may pose a threat to your pregnancy.

What to Do With Pregnancy Test Results

If you take a pregnancy test and it is positive, hCG has been detected and you should be considered pregnant. This, however, does not mean that you will not have an early miscarriage or chemical pregnancy, meaning that your period starts just when you expect it to start. That can make moms really confused and doubt the pregnancy test.

Also in the event of a negative pregnancy test, it does not mean that you are not pregnant, merely that there was not a high enough concentration of hCG found to register as positive. That means a test in two days might produce a different result or even the same result and yet you are still pregnant.

This is why early pregnancy tests can get so confusing. This often has women calling their doctor’s or midwife's offices to ask for advice or help. All they can do is to offer comforting words and or the option to retest.

Retesting, if done immediately, is not the solution. In fact, it can be damaging to one’s ego if you’re really trying to get pregnant. You need to wait. As hard as that is to hear – put down the pregnancy tests and walk away, if only for a few days. Since hCG rapidly increases in pregnancy, a few days can make all the difference in the world, the same is even truer for a week. These days can be an eternity. Trust me, I know. When you want to be pregnant, you want to be pregnant now. With a little faith and patience, early pregnancy tests can be beneficial, as long as you know what you’re getting in to when you take one.



Nerenz RD, Butch AW, Woldemariam GA, Yarbrough ML, Grenache DG, Gronowski AM. Clin Biochem. 2015 Nov 2. pii: S0009-9120(15)00507-X. doi: 10.1016/j.clinbiochem.2015.10.020. [Epub ahead of print] Estimating the hCGβcf in urine during pregnancy.

Pregnancy Tests. Any Lab Test Now. Last Accessed November 11, 2016.

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