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Should You Shake A Pregnancy Test?

No one likes waiting around in the bathroom while a home pregnancy test does its magic. (Pro tip: set the test down and throw out some old cosmetics. I once found a tube of mascara that had turned into cement.) What if the anticipation was too much, and you unconsciously shook the test, like you'd shake a piece of wet fabric to help it dry faster? Now you're wondering, can shaking a pregnancy test affect the results?

Today's Parent compared home test brands and their instructions. Not one of them mentions shaking the test. All of them require you to do the hardest thing — and simply wait. Romper spoke with Dr. Marcy Maguire of Reproductive Medicine Associates of New Jersey, and she writes in an email interview that shaking a test is absolutely not helpful. According to Maguire, shaking "will not help the urine to absorb into the test strip and the shaking motion may actually shake the urine out of the test, causing a false negative result." So follow the pro tip above, and back away from the test.

Maguire writes that "the most common cause of a false negative urine pregnancy test is performing the test too early," so make sure to wait until after you've missed your period before testing — no matter what claims the manufacturer makes.

Some tests, like First Response, claim to be able to detect a pregnancy six or even seven days before a missed period, but read the fine print: the manufacturer noted that the test is more accurate closer to your period.

Waiting is difficult, but pregnancy tests are science, not magic. You have to wait for the right time to take them (preferably after your missed period), follow instructions to the letter, and finally, give the test a few agonizing minutes to work. But such is life.

The lesson learned? Pregnancy tests should be neither shaken nor stirred.