How long after a late period should i test

If you’re trying to get pregnant, the best time to take a pregnancy test is one week after you’ve missed your period. Why? Because this is really the best way to prevent a false negative result (a negative test in someone who's actually pregnant) result.

Home pregnancy tests can be used as early as the first day after your first missed period in women with regular/predictable monthly menses. If you have irregular periods, you can administer a test 14 days after intercourse, since you likely can’t pinpoint your exact time of ovulation.

Pregnancy tests detect a hormone called human chorionic gonadotropin (HCG), which is produced in early pregnancy. The production of this hormone begins slowly and increases as the pregnancy grows. Standard urine pregnancy tests will detect the HCG level when it reaches 20-50 milliunits/milliliters.

If you take a test too soon (before you've missed your period), the levels of HCG may not be high enough to detect a pregnancy and it could cause a negative result, even though you're actually pregnant.

I advise my patients to wait at least one day after you miss your period. If you wait one week after a missed period, the chance of a false negative is very low if you have a normal monthly menstrual cycle.

Brand name versus generic pregnancy tests

Home pregnancy tests, both brand name and generic, are very accurate at detecting the HCG hormone and any positive result, even a faint line, can be considered positive. HCG is only produced by a pregnancy; any positive result indicates a pregnancy.

You don’t need a serum (blood) pregnancy test to confirm pregnancy. Both urine and blood detect HCG, although the blood test is more sensitive and can detect HCG levels at much lower levels than a urine test. In certain situations, your doctor may want to perform a blood HCG test but it’s not typically needed to confirm a pregnancy.

Although most tests advertise 99% accuracy, the ability of a particular brand to detect HCG at levels less than 50 ml may vary. Some brands may be better able to detect lower levels of HCG than others. If your HCG level is more than 50 ml, which is the detection rate of most tests, even generic tests will detect a pregnancy accurately.

You should wait to take a pregnancy test until the first day of your missed period. Since HCG is only present once implantation of the egg occurs, there often isn’t enough of the hormone to be detected until you miss your menstrual cycle.

“Pregnancy tests pick up the hormone secreted after implantation, which usually occurs about two weeks after the sperm meets the egg,” says Dr. Culwell. “For women who have regular periods, this usually means that HCG can be detected as soon as you miss a period.”

This, of course, assumes you have a regular menstrual cycle that can be easily tracked and predicted. If this isn’t the case, you may choose to instead track ovulation, or when an egg is released and makes its way to the uterus where it can potentially be fertilized. An at-home ovulation predictor kit can help you track fertilization.

If this method is used, it’s best to take a pregnancy test “approximately 14 days after a documented ovulation,” says Zaher Merhi, M.D., an OB-GYN, reproductive endocrinologist and founder of Rejuvenating Fertility Center with locations in New York and Connecticut.

Signs You Should Take A Pregnancy Test

The biggest indicator it’s time to take a pregnancy test is a missed period. It isn’t the only sign, however. Symptoms that signal it may be time to take a pregnancy test, according to Dr. Merhi, include:

  • Missing a period
  • Breast fullness/soreness
  • Frequent urination
  • Nausea
  • Vomiting
  • Fatigue
  • Abdominal bloating

When Is the Best Time to Take a Pregnancy Test?

You can take a pregnancy test any time of the day. But if there’s a chance you’re early in pregnancy, take it in the morning when your urine is most concentrated so the test can more easily detect the HCG hormone, says Dr. Culwell.

“The best time in the cycle to take a test would be after you have missed a period,” says Dr. Culwell. “This will make it less likely that you might miss an early pregnancy if the HCG levels are too low to be picked up by the test.”

Where To Buy A Pregnancy Test

You can buy a pregnancy test at most drug stores and grocery stores, or even online.

How Soon Can You Take a Pregnancy Test?

At-home pregnancy tests are regulated by the Food and Drug Administration (FDA), meaning their accuracy and labeling is evaluated before they reach store shelves. When it comes to the accuracy of at-home pregnancy tests, research shows if the test is used as directed, an inaccurate result is rare. While false-positive pregnancy test results are uncommon, if you do receive an inaccurate result, it’s more likely to be a false-negative. In this case, it’s likely you’re testing too early, before HCG can be detected.

“For most women who have a regular menstrual cycle, a pregnancy test could be taken on the expected day of the period,” says Dr. Merhi. “The earliest [time to test] would be the expected day of the period; however, I usually tell patients to wait at least a few days (or one week) after the expected day of the period in order to lower the chances of having a false result.”

It’s worth noting that at-home pregnancy tests accuracy claims—many of which advertise an accuracy rate of 99% from the day of the expected period—are based on data used in a sterile laboratory testing environment. If you think you received an inaccurate result, you can either wait and test again a few days later or see your doctor for a blood test, which can detect HCG earlier than at-home tests and has an accuracy rate of 99%.