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Because the urine test might be more sensitive than the hormone specific blood test. 2) A blood test is searching for the substance itself. The liver metabolizes the substance and sends it on to the kidneys in the form of metabolites. It is entirely possible that the liver has completely metabolized a substance, but it is still showing up in the urine as the metabolite. (Think drug tests, for example).

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Q: Why do you test positive on a urine test but negative on a blood test?
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Can you test positive with a urine pregnancy test and negative on the blood?

No not unless your a troll


Got tubes tied and urine tests positive blood test negative what do you think?

Stop taking more urine tests. Repeat the blood test in two weeks.


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sometime hpt gives false positive... if you took a doctor's urine pregnancy test and came back negative then ask for a blood test--a blood test will tell you if you are pregnant or not- even if you have low hcg in your urine-and yes you could still pregnant with all the symptoms---best of health


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Does a positive urine test show faster than a negative urine test?

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Can a urine pregnancy test keep showing negative but be positive on a blood test and be pregnant?

Yes. I don't know how but it can happen. I cannot use the urine preg. tests , I have to have the serum and then it has to be the quantitate not the yes or no one.


What is a inconclusive urine test?

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Why would a urine test come out positive before taking and negative after taking antibiotics for a bladder infection when you are on Mircette Birth Control and started your period a week ago?

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Can getting menstrual fluid that is positive for drugs make a urine test that is negative for drugs into a positive?

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