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Dix Hills, NY
A 22-year-old female asked:

How many days after sex can you get a pregnancy blood test taken? i had one done 19 days after sex and a late period. came back negative. accurate?

1 doctor answer4 doctors weighed in
Dr. Gurmukh Singh
Pathology 50 years experience
Likely: Conception, as defined by the generation of a fertilized ovum, occurs within day or so of the sex. However, it takes about two weeks for the embryo to make enough HCG to produce a positive pregnancy test. Blood test may be done a day after a missed period. Home pregnancy tests should be done 4-5 days after the missed period. If the result is negative repeat the test in 4-5 days. Use first morning urine and follow instructions for the test carefully. If you do not wish to be pregnant, use contraception all the time, every time. You may consider implanted contraceptive, or IUD. Practice safe sex. Get HPV vaccine.

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Last updated Jul 26, 2015

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