The way to determine whether or not you are pregnant by a reported blood test is to look at the level of human chorionic gonadotropin, or hCG, in the blood. Normally, a woman who is not pregnant has a negative blood hCG test result. In contrast, after the fertilized egg is laid, it usually secretes hCG and enters the maternal blood circulation. A blood test with hCG level over 5mIU/mL should be considered as a possibility of pregnancy. Blood test for hCG is the earliest way to detect pregnancy and is also more accurate. However, a single blood hCG test does not mean that a woman is in a successful state of pregnancy and cannot clearly indicate an intrauterine pregnancy. hCG elevation may also be caused by ectopic pregnancy, complete or partial gravida, chorionic carcinoma, trophoblastic tumor of the placenta and other diseases, which can also lead to elevated blood hCG values. In order to confirm the success of intrauterine pregnancy, it is necessary to combine it with ultrasound and other imaging tests. Pregnant women can monitor the changes of blood hCG and progesterone regularly, because in normal pregnancy, blood hCG will increase exponentially with the progress of pregnancy. This indicates a well-developed gestational sac. Ectopic pregnancy cannot achieve an exponential surge of blood hCG over time.