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1057060 tn?1266516726

conception date?

okay so im just trying to figure out my conception date for fun...  my last period was august 11th 09. my first ultrasound was september 29th which said i was 5 weeks and 1 day (almost 2 weeks less than what i was supposed to be). but according to the subsequent ultraounds and the fact that my due date is may 27th i would have been 5 weeks 6 days. is the first ultrasound the most accurate?? when did i conceive? my pregnancy tracker on here says i conceived on the 20th of august, but other calculators ive used have said anywhere from the 29th to the 4th of september. so im really confused.
3 Responses
1039620 tn?1272597604
Earlier ultrasounds are the most accurate. Conception is an estimate as it all depends on exactly when you ovulated, (could have been late) and length of your cycle. If you had an exact 28 day cycle and ovulated exactly on day 14, you would have conceived on or around the 25th of August, however, not many women have an perfect dates, that's why they give you a window of conception.

Unless you were tracking ovulation and know exactly when, there really is no way to know the exact date.
377012 tn?1283969035
roughly you conceived within 2 weeks before your period to 2 weeks after your period, and yes the first ultrasound is usually the most accurate nunless you are too early then the docs take a second one around 8-12 weeks gestation to get a better idea of baby and edd.
1057060 tn?1266516726
ah this is all so confusing haha. i dont think i ovulated on time because if i did then my due date wouldn't be may 27th it would be a week before...so i guess theres really no way to tell. my first ultrasound though only showed a gestational sac and was done at savalife where they have low quality machines, so maybe that had a lot to do with it.
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