When you’re trying to conceive, you become hyper sensitive to every little twitch and twinge that you experience. Suddenly you begin to see signs of pregnancy or babies everywhere. And you can’t help but wonder, “Am I pregnant?” followed quickly by “How early can you take a pregnancy test?” Fear not—we've got the details you need.

It’s easy enough to do an at-home pregnancy test to find out if you have a bun in the oven. But you might want to wait. Taking a pregnancy test too early can lead to a false negative. And as you may soon find out, the cost of those little plastic sticks adds up.

Read on to learn more about how at-home pregnancy tests work, and how soon is too soon to test.

How do home pregnancy tests work?

There are two types of home pregnancy tests available: Digital tests are the ones that state “pregnant” or “not pregnant” and they sometimes indicate how many weeks along you may be. They are typically pricier than the standard “wait for the line” (analog) options (though that doesn’t mean they are more accurate). Analog tests work by showing a plus or minus sign or having a second line appear next to a control line; some options may also indicate pregnancy through a change in colour on the strip. Be sure to read the instructions first, as each test may work a little differently.

Both tests work by measuring the amount of a hormone called human chorionic gonadotropin (hCG); this hormone is only released once an embryo has implanted in the uterus.

In early pregnancy, hCG levels rise rapidly—usually doubling every 48 hours—which means the further along you are, the more accurate the results. Tip: Urine tends to be most concentrated in the mornings so it’s best to test first thing in the morning (if you're scrolling posts on trying for a baby on social, you may see this called FMU—first morning urine).

How early can you take a pregnancy test?

Having a baby is pretty life-changing so we get why you’re anxious to find out ASAP, but testing at the right time matters when it comes to accurate results. Most companies recommend waiting until the first day of your missed period before testing, though some brands claim their early-detection tests are sensitive enough to detect the presence of hCG up to seven days before your period is due.

If you ask the experts, most health care practitioners agree that waiting until a day after your period was supposed to arrive—usually around two weeks post conception— should ensure that hCG levels are detectable. At this point, the fertilized egg will have implanted and the placenta will have started to form, which is what kickstarts the production of the hormone.

If you experience irregular cycles or you’re unsure of how long your cycles typically are, you can test after you’ve passed the number of days that your longest cycle has ever been. For example, if your cycle ranges from 32-37 days, test on day 37 or later.

Should I take another test?

If you tested positive: Congrats! Be sure to follow up with your primary caregiver to get blood work requisitions to confirm the pregnancy. They can also set you up with early screening appointments and answer your questions on what to expect for the journey ahead.

A note on false positives

While it is rare to get a false positive, it’s not impossible. Things that can result in a false positive include a recent pregnancy (whether you had a miscarriage, abortion or just gave birth), an expired test, improper use of the test or if you’re taking certain fertility medications that contain hCG. There are also certain health conditions that may cause your body to produce hCG without being pregnant.

False negatives are far more common. Testing too early, using a test incorrectly or using a faulty test are all factors that can contribute to the error. If your period is still late or you start experiencing pregnancy symptoms, wait three days before testing again. 

So, when can I be sure?

The most accurate way to confirm whether or not you’re pregnant is a blood test. You can actually confirm pregnancy through blood work just a few days after implantation since hCG levels rise so fast.

Waiting on results can be an exciting and stressful time but sit tight! The turnaround time on these tests is typically quick so try to relax; your doctor will be in touch soon.