Dating pregnancy irregular periods
The doctor insisted on dating it by my period even though I told them I was irregular.
At the dating ultrasound, I was shown to be about 8 weeks (exactly what I thought) but they were thinking I would be closer to 18 or something based on my period.
When they use the conception date, they assume you are 2 weeks pregnant at conception, even if you didn't have a period 2 weeks ago.
I have super irregular cycles, like 40-80 days compared to the normal 28.
Compared to a "normal" cycle where ovulation would occur around cycle day 14, my due date was WAY off if using the normal LMP calculation method.
Or in my case, I never got a period after having my second (breastfeeding), so my LMP was over a year before my positive test!
I think this is part of the reason that a dating ultrasound is pretty standard these days.
For example, when I was pregnant with my first I didn't ovulate until around cycle day 70.
It could be nearly 2 weeks off if implantation isn't considered. Would they just take the age of the fetus from an ultrasound and add 2 weeks?Just because your cycles are irregular, I can't imagine that they wouldn't use the first day of your LMP to date you at first, but maybe someone else can give some insight.If your cycle is very irregular they really can't use your LMP because it will be wildly inaccurate.Our first scan measured the baby's size and confirmed that my due date estimation was only 1 day off, meaning the baby was he size of an 8 wk fetus.
Even though I hadn't had my period 8 weeks ago, I conceived on my the same day someone with a normal cycle would have if they had had their period 8 weeks prior.
I knew when I ovulated, I knew when I started testing positive...