As a person who has had multiple pregnancies and only one child birth i just wanted to comment on this. One thing is that What the consider to be positive is a blood pregnancy level of HCG to be above five. However sometimes your urine can have more hormone in it then your blood does and that is why you get a positive on the home test. This is something that needs to be monitored because you can sometimes have what they call a hormonal pregnancy which is where the body produces HCG and there is never a fertilized egg. Also it depends on how far apart the tests were. If it has been a couple days between the home test and the blood test you may have miscarried in the mean time. This is very complicated matter and really needs to be monitored by a doctor! See your OB to see what is going on! Good luck and hope you are pregnant!