4 Weeks Pregnant
Your period is late! Is it time for a home pregnancy test?
Pregnancy tests look for a special hormone in the urine or blood that is only there when a woman is pregnant. This hormone, human chorionic gonadotropin (hCG), can also be called the pregnancy hormone.
HCG is made in your body when a fertilized egg implants in the uterus. This usually happens about six days after conception. But studies show that the embryo doesn't implant until later in some women. The hCG levels increase drastically with each passing day you are pregnant.
Most home pregnancy tests are able to detect the pregnancy hormone hCG 14 days after fertilization. However, the longer you wait, the more accurate they become. Waiting one week after a missed period will usually result in a more accurate answer.