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Had Unprotected Sex And Got Pregnant. How To Find Out Conception Date?
Question: Hi,I am Currently pregnaant. The first day of my last menstrual period was Nov, 16th 2012. I had unprotected sex with a different guy on Dec 8th 2012. I found out i was Pregnant on Dec 20th 2012. as per my sonogram it shows that i am 13 weeks and 2 days pregnant as of today. is there a possiblity that this pregnancy is from the dec 8th intercourse? im hoping not. its driving me insane.
Hello XXXXXXX
Thank you for your query.
As per your last menstrual period ( 16th November ) - you are 14 weeks and 3 days pregnant.
( Weeks of pregnancy are counted from the last menstrual period, not the date of ovulation / conception ).
However, by ultrasound you are 13 weeks and 2 days pregnant.
Ultrasound in the first trimester is 95 % effective, with error margin of 6 days.
Do you have an earlier scan, that would be more reliable?
Also, I would like to know if your periods were regular or not, that could affect the date you ovulated and hence conceived.
As per your period on November 16th, you should have ovulated on November 30th approximately, however, from your ultrasound you are a week behind your dates, so it could very well be that conception occurred on 8th december.
The only conclusive way to determine this, apart from the game of numbers , is to have a DNA paternity test.
More details of your earlier scans and menstrual cycles, and the other dates of sexual activity apart from 8th December, would help.
Please take care, and do not stress out.
Dont let it affect your pregnancy.
Write in , and feel free to ask further questions.
Thank you for your query.
As per your last menstrual period ( 16th November ) - you are 14 weeks and 3 days pregnant.
( Weeks of pregnancy are counted from the last menstrual period, not the date of ovulation / conception ).
However, by ultrasound you are 13 weeks and 2 days pregnant.
Ultrasound in the first trimester is 95 % effective, with error margin of 6 days.
Do you have an earlier scan, that would be more reliable?
Also, I would like to know if your periods were regular or not, that could affect the date you ovulated and hence conceived.
As per your period on November 16th, you should have ovulated on November 30th approximately, however, from your ultrasound you are a week behind your dates, so it could very well be that conception occurred on 8th december.
The only conclusive way to determine this, apart from the game of numbers , is to have a DNA paternity test.
More details of your earlier scans and menstrual cycles, and the other dates of sexual activity apart from 8th December, would help.
Please take care, and do not stress out.
Dont let it affect your pregnancy.
Write in , and feel free to ask further questions.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
MY PERIOD IS EXACTLY 30 DAYS APART. AND THEY HAVENT BEEN IRREGULAR. MY FIRST ULTRA SOUND WAS ON FEBRUARY 11TH. AND I WAS TOLD I WAS 11 WEEKS AND 2 DAYS FROM THAT DATE. I TOOK A HOME PREGNANCY TEST ON THE 18TH OF DECEMBER AND IT CAME BACK POSTIVE, WHICH WAS 10 DAYS FROM DEC 8TH. IMA LITTLE SCARED BECAUSE I CANT GO ON WITH THIS PRENANCY IF ITS FROM THE DEC 8TH PERSON
IS THERE ANY WAY A PATERNITY TEST CAN BE DONE BEFORE I GIVE BIRTH?
IS THERE ANY WAY A PATERNITY TEST CAN BE DONE BEFORE I GIVE BIRTH?
Hi XXXXXXX
Even from your first ultrasound ( the one on february 11th ), you were one week late, as you should have been 12 weeks and 3 days, but you were more than a week behind.
Based on the details, unfortunately, you cannot rule out pregnancy from the December 8th act.
Yes, most definitely, paternity tests can be done as early as 12 weeks of pregnancy.
Even from your first ultrasound ( the one on february 11th ), you were one week late, as you should have been 12 weeks and 3 days, but you were more than a week behind.
Based on the details, unfortunately, you cannot rule out pregnancy from the December 8th act.
Yes, most definitely, paternity tests can be done as early as 12 weeks of pregnancy.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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