Pueblo, CO
A 23-year-old female asked:
what if i don't know my lmp how will a doctor determine my conception date?
1 doctor answer • 1 doctor weighed in

Dr. Christina Adberg answered
Obstetrics and Gynecology 26 years experience
Ultrasound: First trimester ultrasound is very accurate at pinning down conception date within about a week or so.
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Similar questions
NC
A 23-year-old female asked:
If my estimated due date is nov. 19, what is my range of possible conception dates?
1 doctor answer • 3 doctors weighed in

Dr. Gerard Honore answered
Fertility Medicine 29 years experience
2/26/2012: February 26th is the estimated conception date. Ranges cannot be estimated reliably, they can only be guessed, it's working backward form a simple arithmetic formula.
5592 views
A 42-year-old member asked:
Need to know how to calculate conception date from due date?
1 doctor answer • 1 doctor weighed in

Dr. Edward Jacobs answered
Obstetrics and Gynecology 46 years experience
Naegle's rule: By universal convention, a pregnancy is dated in weeks since the date of the last menstrual period. The due date is 40 weeks from the first day of the last period or approximately 38 weeks after date of conception. Your OB can give you a better answer after your first early ultrasound around 8 weeks....
5480 views
A 30-year-old member asked:
Is a date of conception due date calculator recommended?
1 doctor answer • 1 doctor weighed in

Dr. Alan Patterson answered
Obstetrics and Gynecology 42 years experience
U can: Ask your OB he or she can figure it out based on how often your periods are and when u are due.
5502 views
A 43-year-old member asked:
Explain due date based on date of conception?
1 doctor answer • 2 doctors weighed in

Dr. Neeoo Chin answered
Fertility Medicine 40 years experience
Due date: The normal term pregnancy last 40 weeks. This is calculated from the last menstrual cycle. The last menstrual cycle calculation relies upon the fact that ovulation occurred on day 14. But if calculations are from the date of conception then the pregnancy is only 38 weeks.
5570 views
A 43-year-old member asked:
Tell me how do you calculate date of conception?
1 doctor answer • 1 doctor weighed in

Dr. Edward Jacobs answered
Obstetrics and Gynecology 46 years experience
Depends: Conception usually occurs about 14 days prior to the onset of the next expected period. If the periods are 28 days apart, conception occurs around day 14. If the periods are 32 days apart, then conception occurs on day 18 (32 minus 14 = 18) etc, etc.
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Last updated Mar 2, 2014
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