QuestionHi Dr.,
Thank you so much for your valuable time and answer to my question.
Question: If estimated conception date from a 9 week Ultrasound dates conception on or about 8/1/2011, + or - several days in either direction, do you think it would be possible for conception to have occurred 16 days previous to 8/1/2011 (exact date being 7/16/2011). Based on the extensive reading I have done regarding u/s reliability in the first trimester, sperm viability, ovulation/cycle variability, I would not think 7/16/2011 would fall within the margin of error. Did want to get a professional medical opinion though.
Thanks again and have a great day!
AnswerDear Chamberlin
If you have your cycle every 28-30 days then it is a very remote possibility that your pregnancy dates back to 7/16. However; if your cycle is every 30 days or more then pregnancy may date back to this date.
Although it is difficult to explain by typing on the keyboard, calculations depend on the fact that the period from the first day of the cycle till ovulation is 14 days with 2 days margin in both directions which is fixed regardless the length of the cycle.
I hope these info are helpful and i wish you good luck
