Take a pregnancy test one to two weeks after having unprotected sex. This is the time it takes for the egg to meet the sperm and for fertilization and implantation to take place. Sperm will survive in the uterus for three days and this is the time within which fertilization will take place in the fallopian tube. Then, the fertilized egg will move from the fallopian tube to the uterus for implantation to take place. Women may experience implantation bleeding, which may be perceived as menstrual bleeding and women may think they are not pregnant. After implantation, the body prepared for pregnancy by releasing the human chronionic gonadotrophin hormones that is responsible for the life of the pregnancy. This is the hormone that will be tested for by a home pregnancy test or blood test. The human chronionic gonadotrophin hormone is present in the body fluids of the mother and is tested for in a blood test or a urine test at home. Since it takes this long for a pregnancy to occur, do not take any more time to test for pregnancy as you may not need the test to prove that you are pregnant afterwards.