While it might seem like peeing on a stick will quell these fears, in some cases if you take a test too soon, it could mess with the accuracy, says Michael Guarnaccia, MD, MPH, FACOG, a double board-certified reproductive endocrinologist and Ob/Gyn at Extend Fertility in New York City. And having a possibly wrong test result sounds more stressful than not knowing at all.
In truth, there's nothing wrong with taking an unnecessary test. "As long as you know the limitations of the tests — a negative test before a missed period isn’t always accurate — then all you have to lose is your own anxiety," Dr. Guarnaccia says. "And the cost of the test!" But if you're hovering in front of the family planning aisle of the drugstore, or stressed about possibly being pregnant, here are four questions to keep in mind:
Did you have unprotected sex or experience birth control failure recently?
Even when contraceptive methods are used perfectly, they still come with an inherent failure rate, Dr. Guarnaccia says. "A broken condom or a missed pill around the time of ovulation could lead to an unintended pregnancy," he says. Usually, it takes two to two-and-a-half weeks past a "birth control failure incident" before you know if a pregnancy occurred, he says. If it's been 72 hours since your birth control failed, then emergency contraceptives can be used to prevent pregnancy, he says.
Did you miss your period?
"The optimal time to take a pregnancy test is after you've missed your period," Dr. Guarnaccia says. A pregnancy test is designed to detect the presence of the hormone human chorionic gonadotropin (hCG) in someone's urine. Around the time of a missed period, the hormone reaches a concentration that's great enough for the test to pick up on it, he says.
That means, if you take a test on the early side, then you may not have enough of the hCG hormone for the test to register it, which could result in a false negative. Ideally, you should wait a couple weeks after having unprotected sex before taking a pregnancy test — doing it immediately after isn't really helpful, Dr. Guarnaccia says.
Have you experienced any symptoms?
In the early stages of pregnancy, you may notice some symptoms around the time of a missed period, Dr. Guarnaccia says. Some of them actually mimic period symptoms, so it can be tricky, but be on the lookout for mild cramping, spotting or light bleeding, nausea, breast soreness and engorgement, and nipple soreness, he says. Those symptoms may indicate that you're pregnant, in which case it'd be a good idea to take a test.
Can you wait until the morning?
First thing in the morning is when the hCG concentration is the highest, so it's when you have the lowest chance of a false-negative test, Dr. Guarnaccia says. "Despite the fact that home urine pregnancy tests are generally accurate, there is still a possibility of a false-negative result depending on the stage of the pregnancy and the timing of the test," he says. If you have a negative urine test and still don't get a period, re-take the test in a few days. But in order to increase your chances of an accurate test, and possibly give yourself time to think, it's probably best to sleep on it and wait until morning.