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"How can I tell if I'm pregnant?"

ZocdocAnswersHow can I tell if I'm pregnant?


if both blood and urine pregancy test how is it one will come out negative and the other positive. 5 urine test positive but negative blood test


A pregnancy test aims to detect the presence of the beta subunit of human chorionic gonadotropin (hCG) found in urine and blood. hCG is a hormone that is produced by the placenta of a pregnant woman. Although hCG is a reliable marker of pregnancy, it cannot be detected until after implantation, which occurs six to twelve days after fertilization. If the test is performed during the very early stages of pregnancy, this results in false negatives. Blood tests can detect a pregnancy earlier than a urine pregnancy test. Urine prgnancy tests are around 97% accurate when done correctly. But a blood test is more accurate, but not necessarily more sensitive because the results depend a lot on the lab and technique of the blood test performed. False positive pregnancy tests are rare but they may occur for several reasons. These include: chemical pregnancy that is basically an early miscarriage, missed reaction time by allowing the test sit for too long, a faint evaporation line as the urine crosses the test being mistakenly interpretted as a positive result, and use of drugs (i.e., women given an hCG injection as part of infertility treatment). To confirm or rule out pregnancy, I would suggest a visit with an OBGYN who can examine your cervix and order another blood test and/or an ultrasound.

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