Eager parents-to-be are not famous for their patience, especially when it comes to checking — and rechecking — whether or not their baby-making efforts have paid off. If you're among their ranks, chances are you've stockpiled home pregnancy tests and use them regularly.
But though they're an affordable, easy-to-use and convenient way to find out if you're expecting, home pregnancy tests can be confusing, especially if you're very early in your pregnancy. Here's a guide to deciphering what those little lines or plus signs mean.
Depending on what kind of pregnancy test you use, you'll see a plus or minus sign or, more commonly, a line or two in the window that reveals the results. While the way the results are displayed varies between tests, they all detect the same hormone — human chorionic gonadotropin (hCG). HCG is the hormone produced by cells that will become the placenta.
Make sure you read the instructions on the pregnancy test packaging carefully so you know exactly what you should look for. A sensitive pregnancy test can detect hCG in your urine as soon as 8 to 9 days after ovulation, but most home pregnancy tests are not that sensitive. It's best to wait until the day of your missed period.
If you're pregnant but very early in your pregnancy, the line or double line on your pregnancy test will likely be barely visible, like a smudge of chalk. If you're farther along and the hormones are flowing, the line or lines will resemble marks drawn with a Sharpie.
If there's no line or positive result, it doesn't necessarily mean you're not pregnant (though that is a possibility). Instead, it could simply mean that there's not enough hCG yet for the test to detect. This is called a false negative result. The hCG level doubles approximately every 2 days — so the chance of a false negative occurring decreases the longer you wait to test.
A very faint line on a pregnancy test usually means that implantation has occurred and you're in the early stages of pregnancy. But you'll want to test again a few days or weeks later to see if that line has become thicker and darker, meaning your pregnancy is progressing — and you can safely start getting excited!
It is possible to see a faint line on your pregnancy test and get your period a few weeks later, meaning that you're not actually pregnant, or were only briefly pregnant. This doesn't mean the test didn't work, but you might have experienced a very early and common pregnancy loss called a chemical pregnancy. It could also indicate other kinds of early pregnancy losses like an ectopic pregnancy.[1]
As upsetting as it can be, you probably never would have realized what had happened if that faint line hadn't clued you in, and the event will have no impact on your ability to get pregnant again.
If the results of your home pregnancy test are confusing or unclear, contact your OB/GYN to get a blood pregnancy test to confirm the pregnancy. This test measures the exact level of hCG in your blood and if there is any concern about the health of the pregnancy, the test can allow your doctor to trend the levels to ensure all is progressing well in the early stages.