Hi girls, this is my first post. I think I'm 8 weeks & 4 days (based on LMP) but my cycle is normally 35 days so when ever i look on the net at pregnancy calculators i get different conception dates & different due dates. Does anyone know how accurate the first scan is in telling you how pregnant you are. I read that they can tell to within 1 week? According to my doctor i am due 15 May 06 but i will be prepared to be 1 week late cos i conceived 1 week later. ????????????