- There are two main types of
pregnancy tests: urine and blood tests. - Take a home urine test after your next missed period — anywhere from 14 to 18 days after conception.
- Blood tests are more sensitive and can tell you if you're pregnant 6 to 14 days after conception.
You have two options when it comes time to see if you have a baby on board.
The most common is an at-home urine pregnancy test, available over the counter, though you can take a urine
"Both tests check for a hormone called human chorionic gonadotropin, or hCG," says Crystal Newby, MD, of Kansas City Ob-Gyn. "This hormone is produced after a fertilized egg attaches to the wall of your uterus."
The egg typically attaches 6 days after fertilization, at which point, hCG levels in your blood and urine will increase for the next 6 to 10 weeks. Once hCG levels are high enough, you can expect an accurate reading, but not before then.
When should you take a blood pregnancy test?
Depending on a woman's cycle, a blood test can detect pregnancy between 6 and 14 days after conception.
Blood tests for pregnancy are more sensitive to hCG than home pregnancy tests. They can detect this hormone in low quantities and tell you if you're pregnant sooner than a home test.
While blood tests can provide results sooner than home pregnancy tests, they are usually more expensive and take longer to provide results because the blood must be sent to a lab for analysis.
If the lab is in-house then it will take a few hours. But if the lab is at a different location, it could take several days to learn the results.
When should you take a home pregnancy test?
Most home pregnancy tests advise you to take the test after you miss your next period. If you have a standard 28-day cycle, you'll be most fertile two to three weeks before your period.
So if you get pregnant during that fertility window, you'll need to wait at least 14 to 18 days after conception to take a home pregnancy test.
If you get a negative result and suspect you're pregnant, check the instructions on the box. Home pregnancy tests typically recommend retaking the test 5 to 7 days later, when the hCG levels in your body will be higher.
This type of result is called a "false negative." Sometimes you can receive a false negative result if you take a pregnancy test too soon when your hCG levels are too low for the test to detect them accurately.
Moreover, recent miscarriages, fertility drugs, and rare hCG secreting tumors can interfere with the results of at-home urine tests. If you receive conflicting results after taking a home pregnancy test multiple times, doctors recommend a blood test.
Best at-home pregnancy tests
We test and recommend the best at-home pregnancy tests. Check out our picks:
- Best overall: First Response Early Result, $9.22 on Amazon
- Best test strips: Pregmate Pregnancy Test Strips, $21.95 on Amazon
- Best digital: Clearblue Digital Pregnancy Test with Smart Countdown, $27.48 on Amazon
- Best quick result: First Response Rapid Result, $8 on Amazon
How accurate are pregnancy tests?
Blood pregnancy tests are considered by doctors to be 99% accurate. Quantitative blood tests (also called beta hCG tests) are the most accurate blood tests and can help doctors tell the exact age of the fetus and play a role in detecting any abnormalities.
If you follow directions, home pregnancy tests are an estimated 97% to 99% accurate. If you perform a urine pregnancy test in a lab setting, like at your doctor's office, the accuracy will be closer to 99%. It's important to make sure that you check the expiration date on your home test, as it can affect the accuracy of the results.
After taking either a blood or urine test, it's important to confirm the pregnancy with an early ultrasound.
Insider's takeaway
Home pregnancy tests can provide results faster and be more convenient than a blood test. But you'll probably have to wait longer to receive accurate results.
You can expect accurate results from a blood pregnancy test as soon as 6 to 14 days after conception. Because the test must be analyzed in a lab, it could take up to several days to get the results.
To get the most accurate reading from a home urine test, wait until your missed period. This can come anywhere between 14 to 18 days after conception. If you get a negative result, you can try taking a home test again in 5 to 7 days to see if you have higher amounts of detectable hCG in your body.
Blood tests are considered to be 99% accurate, while home pregnancy tests are around 97% to 99% accurate. Regardless, you should confirm your results by getting an ultrasound.