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Can Blood Test Accurately Determine Pregnancy?
Hi, For the past month or so I ve had on and off nausea, light headedness, and my breast have grown like crazy, and I ve gain weight. I took two at home test but they came back negative. I m on some medications that my docs told me Don t by any means take if you become pregnant . Would a blood test give me a 100% correct answer? My sister had a 12 week miscarriage and didn t even know she was pregnant. Had normalish periods and all her test were all negative. Help Please
Mon, 9 May 2016
Hallow Dear,
I do appreciate your concern. In fact the first cardinal symptom of pregnancy is missing a period. From your history, it is not evident whether you have missed your period or not. About a week after missing a period the other symptoms like nausea & vomiting, frequent urination and breast symptoms start.
However, the pregnancy diagnosis has to be confirmed by pregnancy test. Such test on urine may report false negative if performed too early. The blood tests are very sensitive and specific in which serum Beta hCG is measured. Values under 5 report no pregnancy while values above 25 confirm the pregnancy. These tests are positive even few days before missed period.
If Beta hCG test also reports under 5, you are not pregnant. Please then try to evaluate for some other cause for your symptoms. It may be even stress.
I hope this satisfies you.
Dr. Nishikant Shrotri
I do appreciate your concern. In fact the first cardinal symptom of pregnancy is missing a period. From your history, it is not evident whether you have missed your period or not. About a week after missing a period the other symptoms like nausea & vomiting, frequent urination and breast symptoms start.
However, the pregnancy diagnosis has to be confirmed by pregnancy test. Such test on urine may report false negative if performed too early. The blood tests are very sensitive and specific in which serum Beta hCG is measured. Values under 5 report no pregnancy while values above 25 confirm the pregnancy. These tests are positive even few days before missed period.
If Beta hCG test also reports under 5, you are not pregnant. Please then try to evaluate for some other cause for your symptoms. It may be even stress.
I hope this satisfies you.
Dr. Nishikant Shrotri
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