I was recorded 21 weeks and 5 days by ultrasound on the 24 march 2014. So when was my conception date ?

THe best guess that can be made has a two week plus or minus window. Meaning they can only guess to a 28 day period.

If you are worried about an exact date because you slept with more than one man that month... a DNA test will be required after the birth of the child to determine who the fater is.

Most women worried about an exact conception date do so because of that reason.

Hi khudo,

Best estimate would be around early November, but as smoothy said, it can only be an estimate since women can vary as to when they ovulate in a cycle. A better indicator would be dates from an early scan, but again, it can't give you an exact day.

As noted, there is no way to know one exact date. Nor does it really matter, Conception dates are estimates, and are give or take a week, sometimes more.