The definitive guide to pregnancy tests

The definitive guide to pregnancy tests

Think back to the first time you took pregnancy tests. Were you anxious? Excited? Terrified? Optimistic?

For me, I was in the communal bathroom of my college dorm room crossing my fingers for a negative result. Though I wasn’t ready for a baby, I could imagine a different experience for someone who was.

Regardless of the result you’re hoping for, taking a pregnancy test can be very emotional.

Though the little test can be a life changing experience, there is a lack of knowledge surrounding how to take a pregnancy test, what the results mean, and the truth behind facts and myths related to them.

We’re here to clear things up about the confusion surrounding pregnancy tests.


There's no such thing as a stupid question. 

Let's first address the elephant in the room: the most common questions we get about pregnancy tests...

How soon can I take a pregnancy test for accurate results?

The answer to this question depends on the type of test you’re taking and your menstrual cycle.

It’s important to note that there are two kinds of pregnancy tests: blood tests (usually happens at the doctor) and urine tests (peeing on a stick). Both types measure a hormone called human chorionic gonadotropin (hCG) that quickly enters the picture after the first few days of a pregnancy.

Urine tests are more common than blood, as they can be taken in the comfort of your own home and are usually less expensive. They typically are most accurate three days before your missed period, or two weeks after conception.

Conversely, blood tests can detect smaller amounts of hCG in your blood, meaning you can get accurate results earlier (7-12 days from possible conception).

However, while you might be eager to know the result, levels of hCG (which is what is detected in your urine) increase the longer you wait to test.

Another thing to consider is that ovulation is not clockwork, and this can affect the time that hCG can be detected.

Because of this, the accuracy of pregnancy tests will vary from person to person, which is why we like to take two and wait until the first day of our missed period, just in case.

Will my birth control affect pregnancy test results?

Good news: birth control does not interfere with the results of your pregnancy test. And, since birth control isn’t 100% effective in preventing pregnancy, it’s always good to test every now and then to be sure if your period is irregular or you’re late.

What causes false results?

Although home pregnancy tests are proven over 99% accurate, they're not perfect. False results do happen. A few things that might lead to a false or invalid pregnancy test result include:

Evaporation lines: each brand is different, so often times certain factors can lead to unclear evaporation lines that can be mistaken for a positive result. Be sure to read the instructions of your pregnancy test to find out how long to wait to check the result. Additionally, checking the instructions is important for avoiding false negative results as you may miss the reaction time.

Recent miscarriage or abortion: If you’ve recently had a miscarriage or abortion, this means you’ve recently had high levels of hCG in your urine. While these levels decrease, it is at a slower rate, and takes 19 days on average for the hormone to completely leave your system.

Date of pregnancy test: Believe it or not, pregnancy tests do have expiration dates and being unaware of them could lead to false positive or negative results. Typically, pregnancy tests are fine to use 2-3 years after they’re manufactured, but be sure to check the box for an expiration date.

Ectopic pregnancy: An ectopic pregnancy happens when a fertilized egg implants itself somewhere outside the uterus, usually in the fallopian tubes. Unfortunately, ectopic pregnancies don’t become normal pregnancies and instead are medical emergencies, as they can be harmful to your body. That being said, it is possible to get a false positive test result if you have an ectopic pregnancy, as it still causes high levels of hCG.

User error: We're only human, after all! Pregnancy tests come with specific instructions. Common mistakes that people make include peeing on the wrong side of the absorbent strip, not peeing on the strip long enough, waiting too long to read the results (or not waiting long enough) - the list goes on. Try to take a deep breath before you test, read the instructions, and if you have any doubts, take another. 

Will taking Plan B affect my pregnancy test results?

Plan B is an emergency contraceptive, and should be taken within 72 hours of possible conception. It will not affect the results of your pregnancy test. Because pregnancy tests are not accurate 72 hours after conception, Plan B does not interfere. 

Will being on my period affect pregnancy test results?

Nope! Since pregnancy tests detect the hCG hormone in your urine, it has little to do with your period. Also, getting your period is a sign that you do not need to take a pregnancy test. If your period is irregular, click here for some times on how to know when to test.

How do I know if I should take a pregnancy test?

If you’re questioning it, you probably should. Peace of mind is priceless. Think of it this way: no form of birth control is 100% effective and mistakes happen. It’s better to know early and either be relieved that you’re not pregnant or think about what you’re going to do moving forward.

Of course if you’ve missed your period, your boobs hurt, or you’re not feeling like yourself, your body is telling you to take a pregnancy test. It can be scary, which is why we suggest getting into the habit of taking tests regularly. This might sound crazy, but like we said, errors do happen and you’ll feel much better knowing the result, regardless of what it is.

Let's debunk some pregnancy test myths, shall we?

While there are a lot of questions surrounding pregnancy tests, there are also a lot of myths about them. We decided to get to the bottom of all pregnancy test rumors and deliver the answers that women deserve.

what is the best pregnancy test

Myth #1: Pregnancy test results are immediately accurate

We can’t stress the invalidity of this one enough. If your body doesn’t realize it is pregnant yet, how can we expect a stick you pee on to tell you if you are? It is so important to wait until you’re supposed to get your period to test. Otherwise, your result probably means nothing. We know it’s hard, but hang in there and wait it out.

Myth #2: New urine tests can also confirm the sex of the baby

While technology is pretty impressive in this day and age, we aren’t quite there yet. Unfortunately, you’ll have to wait until you’re 16-20 weeks in to hear the sex from your doctor. Buying gender tests at the drugstore are simply a waste of your money.

Myth #3: Digital tests are more accurate than non-digital ones

Once you’ve missed a period, all pregnancy tests have about the same accuracy. Because women should wait until they miss a period to take a test (to avoid a false result), digital tests are no more or less accurate than non-digital.

Myth #4: There is no bad time to take a pregnancy test

Believe it or not, there is a bad time to take a pregnancy test. Every woman should wait until after she missed her period to test. If you have an irregular period, wait to test until you’ve passed the longest menstrual cycle you usually have. It’s also important to consider the time of day you’re taking the test.

The doctors we spoke to explained that taking a pregnancy test early in the morning helps avoid the chances of an incorrect result. This is because your urine is more concentrated when you wake up before drinking water, which makes it easier for pregnancy tests to detect hCG.


Make sure to pause to get all the details! #fyp #pregnancy #pregnancymyths

♬ déjà vu sickmix - Sickickmusic

Myth #5: There’s no such thing as a false-positive

Although not nearly as common as a false negative result, false-positive pregnancy test results do happen. A number of factors can lead to a false-positive result including evaporation lines, a previous miscarriage/abortion, and certain medications to treat infertility.

Myth #6: Stress can cause a false-positive test result

While waiting for your result to show up can be stressful, stress will not have an effect on the levels of hCG in your urine and, in turn, not impact the accuracy of your result.

Taking a pregnancy test can be scary and intimidating enough on its own, so don’t believe everything you read and hear about how it should be done.

Where do pregnancy tests come from, anyway?

Now that we have the facts laid out, let’s deep dive into the origin of pregnancy tests and some surprisingly cool facts you probably don’t know about them.

Time for a brief history lesson...

Let us take you way back to 1350 BC. Essentially, Egyptian women would urinate on bags of barley and wheat each day and wait to see if they grew. If they both grew, it was believed this woman was pregnant. Can you imagine? The patience! Believe it or not, scientists actually found this to be a pretty accurate prediction. If you think peeing on barley and waiting a week for it to sprout is crazy, keep reading.

Say hello to “Piss Prophets.” In the Middle Ages, Europeans believed a woman to be pregnant if her urine did things like change the color of a leaf or rust a nail. Unlike the Egyptians, there wasn’t much science to back this logic. In 1937, German scientists discovered that injecting urine into a sexually immature female mouse would cause its ovaries to grow. Crazy, right? This was actually a huge breakthrough as far as the science behind pregnancy tests, as it proved that hCG caused mice to ovulate.

Meet Winx Health (formerly known as Stix)

As you can tell, pregnancy tests have had quite the glow up....

pregnancy-ovulation-test-combo We certainly can’t imagine peeing on some grains as a means of finding out you’re pregnant. In fact, we can’t even imagine going out to the store to buy a pregnancy test today. That’s why we created Winx Health - the discreet, convenient, and accurate pregnancy test. 

While pregnancy tests have evolved big time since 1350 BC, Cynthia and I still saw an opportunity for improvement. Cynthia ran into her boyfriend’s mom in the store while buying a pregnancy test (talk about Sunday scaries). I had the cashier jokingly wish me good luck when I was buying mine. The nerve! If you’ve had a similar experience, you know how humiliating it is. For those who haven’t, we created Winx Health to ensure you are never a victim of pregnancy test shaming.

After doing some research, we found that the public embarrassment of buying a pregnancy test was just the beginning of a long list of problems surrounding women’s options. After surveying thousands of women, we found that 70% of them had terrible experiences buying pregnancy tests. Additionally, we observed that drugstores price their tests unnecessarily high. We deserve better. So do you. 

What is Winx Health?

how soon can a pregnancy test work

Winx Health is an at-home, gyno approved pregnancy test shipped discreetly to your door, by us. We deliver our over 99% accurate, adorable, proven pregnancy tests to women all over the country. What’s so discreet about Winx Health? Winx Health comes in a brown envelope with no indication of what is inside. No company name or purchase history, your roommates will have no idea.

How Winx Health Works

A standard Winx Health order includes two pregnancy tests (for peace of mind), a detailed instruction card with information about how to use the tests and what the results mean, and a personalized thank you note from Winx Health founders for supporting our mission. Additionally, Winx Health offers next-day delivery at your convenience. You can choose to order as many tests as you’d like, or try our subscription option. This is great for those trying to conceive and anyone with irregular periods, like us, who test for peace of mind. This provides you with pregnancy tests every 4, 8, or 12 weeks, and you can cancel at any time. We don’t want buying a pregnancy test to be something you even have to think about.

Who is Winx Health for?

No matter the result you’re hoping to get from your pregnancy test, we want to make your experience as private and comfortable as possible. A lot of our customers spend months or years trying to conceive and value the time, money, and energy we save them by providing autoship tests rather than constantly making trips to the store. Conversely, other customers aren’t hoping for a baby and order Winx Health to ensure their birth control is working or in case of a scare. Whether you’re totally comfortable strutting into a drugstore in your hometown or you’re 16 and can’t bear for your parents know you’re sexually active, Winx Health is for you.

By now, you should be a pregnancy test pro. Now that we know what we do about testing and our options, we’ll never turn back. Check out our blog for more resources like this and for any other questions you might have.


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