According to lmp i ovulated dec 2 and i am due aug 25 & according to six week ultrasound i ovulated dec 6 and due aug 29 what information do i go by?

Period first: Your due date is usually determined by the first day of your last period. If that due date differs by 4 or more days from your ultrasound, your doc is likely to change your due date.

August 25: Since the difference between your first trimester ultrasound and your LMP is less than 7 days, the LMP date is used. So if the first day of your last menstrual period was nov. 18 your estimated due date is aug. 25. Only about 5% of women actually deliver on their due date though.