Accuracy of pregnancy dating ultrasound
Generally, ultrasounds which are performed in the first trimester are within 3-5 days of being accurate in terms of assessing gestational age.
This is because although every little embryo is unique, there are still defining characteristics of development which apply to all embryos at particular stages of early gestational development.
It said I was then 5w5d, and I've often wondered if I were actually further along (due to symptoms) or if this is just the way third pregnancies are sometimes.The baby was measuring just a tad over an inch and looking just like a 9 week old should.I too have hear that they are very accurate in the 7-11 week range. I'd been charting, not temps, just CM, sex, and periods to keep track.Nealy mama to T, 5; L, 2; and EDD 12/20/08 -- if the u/s was right!