What is the soonest i can take a pregnancy test if i do not get a period?

Patience...: It can be hard to tell if a woman is pregnant because some of the symptoms seen in early pregnancy can also happen in non-pregnant women. A home urine pregnancy test gives a reliable result if done 3 weeks after sex (3 weeks after when conception might have occurred), or 1 week after missing a regular period. A test can be done anytime, but is not reliable if too early.