Before ultrasound due date was 07/13/15 but after ultrasound due date went to 07/27/15 which is more accurate?? .. took preg.test 11/08 it was neg.

Depends: It depends on when ur ultrasound was done whether it or ur dates r more accurate.The margin of error for ultrasound dating increases as the pregnancy progresses.The first month all fetuses r pretty much the same size but by delivery babies can vary quite widely in size (normal is 5 1/2 pounds to 8 pounds at term).If the ultrasound was done early, it is more reliable. If done late, your dates are.