How to Read an Ovulation Test

If you’re wondering “when should I start testing for ovulation?”and want to know how to interpret the results when you take it, read this quick guide.

By Halle Tecco, MBA, MPH

What is an ovulation test?

Ovulation tests (aka ovulation predictor kits) are clinically proven to identify your fertile window. While different from an advanced digital ovulation test, our midstream ovulation tests can help you identify your most fertile day. Through the use of a midstream ovulation predictor kit, the tests can help you get to know your body and its variations, and identify the time when you're most likely getting pregnant.

After you follow the midstream ovulation test stick instructions, pee on the test or dip the strip in urine, and wait for the test result, take a close look at the two lines. One is the control line (C), which is there to make sure the test worked. The other is the test line (T) that shows the ovulation test result.

Unlike a pregnancy test, two lines alone is not a positive result since your body makes LH at low levels throughout your cycle. A result is only positive if the test line (T) is as dark or darker than the control line (C) line.

Unlike a pregnancy test, two lines alone [while ovulation testing] is not a positive result since your body makes LH at low levels throughout your menstrual cycle.

How To Properly Read an Ovulation Test

Positive: In short, if the test line (T) on the ovulation test stick is as dark or darker than the control line (C), it is a positive test. This means you are in your fertile window, and you'll likely ovulate within 36 hours. If you are hoping on getting pregnant this month, now is the time as you are in your peak fertility window—aka the time when you're most likely to conceive.

Negative: If only the control line (C) on the test shows up, or if the control line (C) is darker than the test line (T), the test is negative (you are not having an LH surge). In this case, try testing again tomorrow to see if you still have a lighter line on ovulation test results.

Invalid: If only the test line (T) shows up, or neither lines show up, the ovulation testing didn’t work. This could mean the absorbent tip wasn’t saturated with enough urine, or the test is damaged or expired (check the wrapper). Grab another test and try again. If you still get a non-accurate result, contact us.

Next up:

• Wondering if you’re ovulating? Begin testing if you are pregnant using our Natalist Pregnancy Test.Learn from women who have used Natalist midstream Ovulation Tests to get pregnant, and find out what positive ovulation test results look like.
• Want the full scoop on the various types of ovulation test kits? Check out The Ovulation Test Cheat Sheet.
• Learn more about testing for your LH surge and our midstream ovulation test sticks.
• Use our free ovulation calculator in the meantime; estimating your ovulation can offer insights into your individual cycle, aiding in its understanding and tracking.