All the pregnancy tests look for a pregnancy hormone in the woman's urine or blood. This specific pregnancy hormone, what is only made in the woman's body when a fertilized egg implants in the uterus. Most of the times this happens around 6 days after conception. Almost all the pregnancy tests claim to tell you if you are pregnant on your next period day. It is much better to wait one week after your missed period to give a more accurate result.
Ovulation, conception and pregnancy tests
Don't forget that every woman has a differtent time schedule for the fertilized egg to implant in the uterus. If your pregnancy test doesn't give a positive result, it doesn't mean you are not pregnant! It is possible you ovulate later than you thought or that the implantation off the fertilized egg took longer than the average.
Pregnancy test sensitivity
The sensitivity of most of the pregnancy tests vary. It is obvious that some testsets will pick up your pregnancy earlier than your period is due. How lower the level of the pregnancy hormone means the test is more sensitive. A testset with a low sensitivity picks up a pregnancy at 6 to 8 days past the ovulation. But most of the women get a positive result around the 9 or 10 days.
Accuracy of home pregnancy tests
Most of the home pregnancy tests are very good and accurate. But this specific accuracy depends on a few things:
Follow the directions on the test and check the expiration date
Wait one week after a missed period to test to have the most accurate result
Some women will need to wait longer, so be patient
The quality of the home test is very important
It is best to let your healthcare provider confirm your pregnancy.
When you take a home pregnancy test
Most of the testsets claim to be 99% accurate on the day you miss your period. Always ask your doctor or healthcare provider for a more sensitive test.