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    Home Pregnancy Tests



    What Affects the Test

    Reasons you may not be able to have the test or why the results may not be helpful include:

    • Taking the test very early in your pregnancy. HCG may not be found. In this case, the test kit may show that you are not pregnant when you really are pregnant. This is called a Reference false-negative Opens New Window result. If you have drunk a lot of fluid, your urine may be diluted and this may also cause a false-negative result.
    • Certain things may cause the test results to show that you are pregnant when you are not pregnant. This is called a Reference false-positive Opens New Window result. False-positive results may be caused by reading the test at the wrong time, letting the test equipment get warm, having protein or blood in the urine, or having hCG hormone in the urine from some other cause.
    • Taking certain medicines, such as chlorpromazine or methadone.
    • Taking fertility medicines that contain human chorionic gonadotropin.
    • Not reading the result at the right time as shown on the instructions. If you read the result too early or too late, the color change may not be accurate, and you will need to retest.


    This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.