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Portland, OR
A 25-year-old female asked:

I have always had irregular periods since menarche (age12). now i'm 25. last few cycle lengths were 36,35,33,40,33,32,42,39,39,39,34 days. should i be concerned about this? which day of my cycle should i take my first pregnancy test,if i am planning?

2 doctor answers4 doctors weighed in
Dr. James Ferguson
Pediatrics 48 years experience
It happens: Some women will opt for BCP's so they can get predictable cycles.From the intervals listed it would be reasonable to wait until 60 days out for a urine pregnancy test if trying. You could wait longer & they are relatively cheep.
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Dr. Gurmukh Singh
Pathology 51 years experience
3 weeks after sex: Conception occurs within day or so of the sex. It takes about 3 weeks for the embryo to make enough HCG for 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.
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Aug 29, 2020

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