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How To Calculate Date Of Conception?
Question: I am Really Curious and need a answer! My LMP was Septemeber 10,2014 at my 1st ultra sound my Dr said baby was a little further along. So 40 weeks after my LMP should have been a Duedate if 6-17-15... But since the baby was growing bigger he set my Due date at 6-11-15... My question is did I just ovulate a few days early that month? Or could i possibly be pregnant by a 1 night stand that happend sept. 8 (3days before my lmp)? As of rite now i am 25weeks 6 days..
Brief Answer:
gestational age is calculated from LMP only ....
Detailed Answer:
Hello,
Thanks for the query to HCM,
Ideally the due date should be calculated from the LMP itself according to the NAEGLE's formula and the date of EDD is rightly estimated to be 17th XXXXXXX 2015.
The first ultrasound which is known as the dating scan estimates the gestational age and EDD according to the HADLOCK FORMULA and estimation and there is always a discrepancy of around 1-2 weeks between the actual dating scan and the LMP estimation. But for all practical purposes , universally LMP has been used as a bench mark for calculating gestational age and all inferences are drawn based on LMp and not on ultrasonological age Usg estimation can be biased and erroneous with regards to subjectivity of the physician who is performing the scan and may vary between two observers , hence LMP is chosen for calculation without bias.
Fot ALL practical purposes as your lamp was 10th september 2014, it is not possible for that one night stand on sept 8th to get you pregnant instead you would have conceived around 24-26th of september as per ovulation period.
I hoep i have answered you query,
Regards
gestational age is calculated from LMP only ....
Detailed Answer:
Hello,
Thanks for the query to HCM,
Ideally the due date should be calculated from the LMP itself according to the NAEGLE's formula and the date of EDD is rightly estimated to be 17th XXXXXXX 2015.
The first ultrasound which is known as the dating scan estimates the gestational age and EDD according to the HADLOCK FORMULA and estimation and there is always a discrepancy of around 1-2 weeks between the actual dating scan and the LMP estimation. But for all practical purposes , universally LMP has been used as a bench mark for calculating gestational age and all inferences are drawn based on LMp and not on ultrasonological age Usg estimation can be biased and erroneous with regards to subjectivity of the physician who is performing the scan and may vary between two observers , hence LMP is chosen for calculation without bias.
Fot ALL practical purposes as your lamp was 10th september 2014, it is not possible for that one night stand on sept 8th to get you pregnant instead you would have conceived around 24-26th of september as per ovulation period.
I hoep i have answered you query,
Regards
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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