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Casper, WY
A 24-year-old female asked:

Is a pregnancy test taken with first morning urine accurate after 40 days since sex . i had my period, on time was just lighter?

2 doctor answers3 doctors weighed in
Dr. Heidi Fowler
Psychiatry 27 years experience
HCG: A home pregnancy test should be accurate at 40 s/P sexual activity.
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Gurmukh Singh
Pathology 51 years experience
Timing of testng: 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.

Related questions

A 19-year-old female asked:
2 weeks and 4 days ago I had sex a week before my period. Period was lighter than normal. Has it been enough time to do a pregnancy test?
Dr. Gurmukh Singh
Pathology 51 years experience
After missed period: You may do the test in a week or so, however, it is usually better to do the test 4-5 days after a missed period. Alternatively, in 4-5 days, you coul... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 22-year-old female asked:
Multiple pregnancy tests negative after more then 4 weeks since sex and 11 days after lighter period that started and ended on time is it safe to say Im not pregnant?
Dr. Gurmukh Singh
Pathology 51 years experience
Likely yes.: To be sure, you should get a blood test for HCG level.
Created for people with ongoing healthcare needs but benefits everyone.
A 23-year-old female asked:
Me and my bf had sex. Used a condom and pulled out. Period on time but lighter than normal. Neg pregnancy test. Am i pregnant?
Dr. Ed Friedlander
Pathology 46 years experience
No: Nothing to suggest you are pregnant. I'm glad you've got someone special, and have taken precautions.
Created for people with ongoing healthcare needs but benefits everyone.
A 27-year-old female asked:
Period shorter & lighter this month. Negative pregnancy test; no unprotected sex. Came on time, but just different. Could i still be pregnant?
Dr. Gurmukh Singh
Pathology 51 years experience
Unlikely: You may do a home pregnancy test and if it is negative repeat it in 7-10 days. Use first morning urine and follow the instructions for the test carefu... Read More
Created for people with ongoing healthcare needs but benefits everyone.
A 24-year-old female asked:
Can I trust a negative pregnancy test 3 months after sex ? I have had all my periods on time , one after plan b being very lighter than normal . no symptoms. Many negative tests. please help?
Dr. Heidi Fowler
Psychiatry 27 years experience
HPT: Yes, you can trust the home pregnancy test. Use of Plan B or other emergency contraceptives can cause menstrual changes but in your case you are stil... Read More
Created for people with ongoing healthcare needs but benefits everyone.
Last updated May 14, 2021

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