Can pregnancy be detected before a missed period

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If you have been intentionally trying to conceive, you are likely aware of the variety of early pregnancy tests currently available. These tests can sometimes detect pregnancy several days before your period is due.

However, just because you can use an early pregnancy test, does that mean you should? It's worth considering a few points before you proceed.

Types of Pregnancy Tests

There are two types of pregnancy tests you can take: urine or blood tests. Over-the-counter home pregnancy tests are urine tests, and doctor's offices frequently use this method as well. Early pregnancy tests are a more sensitive type of urine test. These tests can potentially detect human chorionic gonadotropin (hCG)—the early pregnancy hormone—before your missed period and give you an accurate positive result.

Blood tests are performed in a doctor's office, usually when you have a reason for testing earlier than usual. Blood tests detect hCG and/or the exact amount of it that is present in an effort to look for certain complications, such as an ectopic pregnancy.

While it's true that you can usually take a blood test sooner than a urine test, keep in mind that it usually takes longer to get blood test results.

Pros and Cons of Early Pregnancy Testing

Pros

• Fastest way to test for pregnancy at home

• Helpful if you need to start or stop medications

• Useful in case of birth control failure

• Allows you to begin prenatal lifestyle changes

Cons

• Testing too early can result in a false negative result

• Expensive, if repeated tests are necessary

• Chemical pregnancy could be identified

• Can cause anxiety

Pros of Early Pregnancy Tests

These early detection tests may offer advantages in some circumstances. You may want to discuss your testing plans with your doctor first.

Early Detection

Except for having a physician order an early hCG blood test, which is usually done only when there are medical reasons to detect pregnancy as early as possible, early home pregnancy tests are the fastest way for you to find out whether you are pregnant during a particular menstrual cycle.

The most sensitive tests on the market can potentially give you a positive result four to five days before your period is due, meaning you don't necessarily have to wait for a missed period, or watch for other pregnancy symptoms, to find out whether you are pregnant. However, there is a significant chance of getting a false negative with these tests.

Need to Start or Stop Medications

Very early testing can be helpful if your physician plans for you to start or to discontinue any medications as soon as you discover you are pregnant.

Birth Control Failure

Early pregnancy tests may also be helpful if you were not intending to conceive but had a birth control failure around the middle of your cycle, and you want to know as soon as possible whether you are pregnant so that you can determine your desired course of action.

Pregnancy Lifestyle Changes

A common reason to opt for early pregnancy testing is so that women can be as healthy as possible, including focusing on eating well, taking prenatal vitamins, and avoiding alcohol. If this is your goal, instead of taking early pregnancy tests—which can be negative even if you are pregnant—it may be better to assume that you could be pregnant and adjust your habits doing those few weeks from conception to a missed period.

Cons of Early Pregnancy Tests

For the most accurate results, most experts recommend waiting to take a pregnancy test until the day of a missed period rather than testing early.

False Negatives

The package insert for one of the leading brands of early pregnancy tests states that, when used five days before the expected menstrual period, the test will detect hCG in about 76% of pregnant women. Four days before the expected menstrual period, 96% of women will have a positive result if they are pregnant—meaning 4% may not.

Although it is true that these tests can tell you that you are pregnant in a given cycle, they cannot tell you that you are definitely not pregnant, and there is a significant chance of having a false negative result.

Cost of Repeated Testing

You may be more likely to get a false negative if your menstrual cycle varies in length or if you are not tracking the exact date to expect your period. Additionally, if you take a test when your urine is diluted rather than concentrated, it can throw off your results. In other words, it's better to take a test first thing in the morning rather than after drinking a lot of fluids throughout the day.

Thus, the uncertainty of a negative result may lead you to use multiple early pregnancy tests in each menstrual cycle, and this practice can cost you a considerable amount of money without changing the ultimate answer.

Chemical Pregnancy

Early pregnancy testing increases your chance of detecting very early miscarriages that might otherwise go unnoticed. Often termed "chemical pregnancies," these miscarriages cause you to get a positive pregnancy test but then have your period arrive on schedule or only a few days late, making the test appear to be a "false positive."

Researchers believe that chemical pregnancies are extremely common and rarely indicate any underlying health concerns in the mother. But these conceptions are being detected more often because of the sensitive pregnancy tests now on the market.

If you wait to test until after your period is due, you will have lower odds of noticing a chemical pregnancy. Depending on your outlook, you may prefer to wait to take an early pregnancy test so as to reduce the risk of being disappointed a few days later.

Remember that finding out a few days early is not going to affect whether you actually are pregnant, nor will it affect the outcome of your pregnancy.

Anxiety

Perhaps the biggest drawback to taking early pregnancy tests is the anxiety this practice can create. While we think of anxiety as primarily a mental symptom, the resulting stress hormones the body secretes can be unhealthy physically. If a goal of doing an early pregnancy test is so that you are sure to be as healthy as possible, testing may actually accomplish the opposite of what you intended.

7 Reasons Not to Take a Pregnancy Test Early

A Word From Verywell

Everyone's circumstances are different, and you have to make the decisions that work best for you. Sometimes knowledge is reassuring, and sometimes it isn't. Each person will be different when it comes to the best time to do a pregnancy test. While early pregnancy tests may give you peace of mind in some cases, be sure to talk to your doctor to ensure you're using them correctly to get the most accurate results.