Many home pregnancy tests (HPTs) claim to be 99% accurate on the day you miss your period. But research suggests that most HPTs do not consistently spot pregnancy that early. And when they do, the results are often so faint they are misunderstood. If you can wait one week after your missed period, most home pregnancy tests will give you an accurate answer. Ask your doctor for a more sensitive test if you need to know earlier.
When a home pregnancy test will give an accurate result
depends on many things. These include:
- How long it takes for the fertilized egg to implant in the uterus after ovulation. Pregnancy tests look for the hormone human chorionic gonadotropin (hCG) that is only produced once the fertilized egg has implanted in the uterine wall. In most cases, this happens about 6 days after conception. But studies show that in up to 10 percent of women, the embryo doesn’t implant until much later, after the first day of the missed period. So, home pregnancy tests will be accurate as soon as one day after a missed period for some women but not for others.
- How you use them - Be sure to follow the directions and check the expiration date.
- When you use them - The amount of hCG in a pregnant woman’s urine increases with time. So, the earlier after a missed period you take a HPT, the harder it is to spot the hCG. If you wait one week after a missed period to test, you are more apt to have an accurate result. Also, testing your urine first thing in the morning may boost the accuracy.
- Who uses them - The amount of hCG in the urine at different points in early pregnancy is different for every woman. So, some women will have accurate results on the day of the missed period while others will need to wait longer.
- The brand of test - Some home pregnancy tests are more sensitive than others. So, some tests are better than others at spotting hCG early on.