My dating scan is wrong why
The size of the baby correlates less and less with its age as time goes on.Ultrasound examinations from 12 to 22 weeks are regarded as being within 10 days of accuracy (or up to 10 days earlier or 10 days later than the woman's calculated due date).I think it is more likely to be told girl and then possibly be having boy as, as I understand if they can find no "y" chromosome in the DNA then they automatically say female (XX)..there is a chance that there wasn't enough fetal DNA, therefore no "y" chromosome showing..however, firstly the result should be inconclusive if there isn't enough fetal dna and secondly, yes it happens but would be extremely rare..I have also read somewhere that, if you've had a boy recently I,e, within 18 months then there is a very small chance that there is still a bit of "y" chromosome in your blood so this might give a false male gender result. I've read that too, but my only child so far is a girl.the baby and its heart beat can be detected relatively easily with trans-abdominal and trans-vaginal examination.
Gut feeling this time says boy (it said girl last time, and I have a beautiful 16 month old daughter).
This is because the fetus is growing so quickly that there is a big difference in size from week to week.
Also the fetus cannot bend and twist too much yet, so the length of the body is fairly constant.
Ultrasounds performed after 22 weeks gestation cannot be used to estimate the due date of the baby because the size no longer reflects the age very well.
Even average babies can differ by up to 2 to 3 "weeks of growth";.