When i find out the date of conception..how acurate is that date?

Approximate: Depending on how your due date is determined there may be a large margin of error. Early ultrasound (between 7-12 weeks) is the most accurate and you can work backwards and find a 3-5 day window where you most likely conceived. Later us can be less reliable and be off by as much as 3 weeks in your 3rd trimester. Talk to your OB if you have more specific questions. Take care.