Best Pregnancy Test: Bloodwork or Urine Test?

Updated in February 2022

An at-home pregnancy test can be done after the first day of a delayed period, while a blood test can be done as early as 12 days after the fertile window (before the period is due).

Pregnancy tests sold at the pharmacy have a different testing method, and therefore, if the test is negative but symptoms of pregnancy are present, the test should be repeated 3 to 5 days later. The hormone that this test detects will increase each day, and the test result can become positive after waiting for levels to rise.

It is also important to remember that do-it-yourself tests at home that use chlorine, toilet water, coca-cola, a needle or vinegar are not reliable and should not be used to confirm pregnancy.

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Which exam to do

There are two pregnancy tests that you can do that are accurate and reliable: a blood test completed at the lab and a urine test, which you can purchase at the pharmacy or do at the doctor's office. These tests work by detecting and measuring beta-HCG hormone levels. This hormone will only present in the body during pregnancy.

1. Pharmacy Urine Test

A pharmacy urine test measures the amount of beta-HCG hormone present in the urine and can be completed after the first day of the delayed period. The exam is quick and easy, and will provide a result within a few minutes. It is important to be wary of the result if the test is done before the missed period, as doing the test too early can make hormone detection difficult.

If the test shows a negative result, but there are definite pregnancy symptoms present (like increased breast sensitivity and oily skin), you should repeat the test in 3 to 5 days. To confirm the pregnancy definitely, the woman can opt to complete a blood test, as this test will also tell you how far along you are (based on how high the beta-HCG levels are in the blood).

Learn more about the first signs of pregnancy.

2. Blood test

A blood test is completed in the lab and is the most recommended test for confirming pregnancy. It not only detects the hormone in very small concentrations (which may not be picked up in the urine), but also measures the quantity, which can tell you how far along you are.

To complete testing, you usually do not need to be fasting, however some labs may ask you to be fasting for 4 hours.

Results of the blood test can be determined a few hours later. To be completely accurate, testing should be done at least 1 week after conception, even if the period is not yet delayed.

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Possible pregnancy test results

The possible results of a pregnancy test (pharmacy test and blood test) can include:

  Pharmacy Test Blood test
Positive A darker line or 2 lines over 5 mIU/ml
Negative No change or just 1 line less than 5 mIU/ml
False negative No change or just 1 line between 5 to 25 mIU/ml

Positive result

When the pregnancy test shows a positive result, it means the woman is pregnancy and should start her prenatal care to prepare for the baby's arrival. With a blood test, it is possible to know approximately how far along she is by assessing the quantity of beta-HCG hormone detected.

Enter your beta-HCG result in the calculator below to know how far along you are:


Negative result

If the pregnancy test is negative, but the period continues to be delayed, the test should be repeated 1 week later to confirm the previous result. If the test is negative again, it means that the woman is definitely not pregnant and the reasons for the delayed period should be investigated.

While you wait to complete a pregnancy test, report your symptoms below to assess you probability of pregnancy: