DIY pregnancy tests require you to pee onto a stick, as most of you are aware of. What does a pregnancy test need your urine for? Well, they work by detecting the hormone human Chorionic gonadotropin, which is produced as soon as a fertilized egg starts implanting itself into the lining of your uterine wall. This hormone, often just called hCG, dominates the female body in those early weeks and can be found in the blood and in the urine.
Blood tests for pregnancy are even more accurate than urine tests, and they can be done earlier on before you have even missed your period. So, how soon after a missed period can you take a pregnancy test? Immediately!
At-home pregnancy tests are extremely reliable once a woman has missed her period. The highest concentration of hCG is found in a woman's urine first thing in the morning. That is why the general recommendation used to be that a pregnancy test should be done at that time. But technology has moved on a bit, and modern pregnancy tests can be used at any time of day. If you test too early, it is possible to get a negative pregnancy test and to still be pregnant. If you are on medication containing hCG, false positives are also possible. Generally speaking, pregnancy tests are very reliable. If you have just tested and your test showed that you were pregnant, it's not too early for us to say, Congratulations!