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A 23-year-old female asked:

Hello doc, my last period started august 13th and my cycle is 40 days long. i had protected sex on the 15th of september.ive had 4 blood pregnancy tests on 7 days, 14 days, 21 days and 27 days after said protected sex, all negative.what do you think?

2 doctor answers2 doctors weighed in
Dr. Rebecca Gliksman
Internal Medicine 39 years experience
Would repeat the blood HCG test this week and consider an ultrasound next week if negative. May be stress but have to rule out pregnancy.
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Dr. Gurmukh Singh
Pathology 50 years experience
It at 4 weeks after the episode of sex in question the blood test is negative for pregnancy, it is unlikely that you are pregnant. You may do a home pregnancy test in a week or so, unless you get a period by then. Wish you good health!
Created for people with ongoing healthcare needs but benefits everyone.

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Created for people with ongoing healthcare needs but benefits everyone.
A 17-year-old female asked:
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Created for people with ongoing healthcare needs but benefits everyone.
A 20-year-old female asked:
Had unprotected sex on 21 Feb,got last period on 5 Feb. pregnancy test kits as tested on 18 March negative. Blood test beta HCG <1.20mIU. Pregnant?
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Created for people with ongoing healthcare needs but benefits everyone.
Last updated Oct 18, 2021

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