I have just found out that I am pregnant when taking a test n 23rd January. This would work out right as I had sex with my partner during the time inwould have been ovulating. I had sex with another man which my partner is aware of which was a mistake as we've been together a long time.
I slept with this other person on the 3rd of December and I had my period as I said on the 24th.
this baby is quite large at 28 weeks, he's 3.11 lbs.
But after that at my 13 (actually 14 weeks) and 15 week ultrasound, they moved it back because I was not measuring that big.
Before the advent of routine ultrasound in pregnancy, medical personnel estimated a baby's due date by the date of the last menstrual period and by feeling the uterus and determining the size to see if it matched the given due date.
With transvaginal ultrasound, checking for embryonic development known to occur within a certain time frame more accurately dates a pregnancy.
The tech said it should have been done around 8-11 weeks to be more accurate but they have left it at my LMP ever since.
I had many more ultrasounds and the baby has been on the small side the whole time but I was a small baby too. Your baby has no idea when the "adult/doctor/ultrasound-determined-d-day" is and will come when he or she is ready.