Just got my positive test and im so excited but also clueless about how the due date gets decided. Do they count from last period or from the scan? My cycles are a bit irregular so im confused which one to go by.
Doc told me the standard method is LMP (last menstrual period) plus 280 days. But since not everyone ovulates on day 14, the first trimester ultrasound is the gold standard for confirming due date. Mine shifted by 4 days after scan.
I was wondering same thing! My last period date gave one date and the scan gave slightly different. The doctor said go by scan. Did that happen with anyone else? a bit confusing first time.
I just put my last period date in a pregnancy app and it calculated the due date instantly, also showed weekly updates. But the doc's scan refined it slightly, so trust the scan number in the end.
Usual way is count from the first day of your last period and add about 40 weeks. But the early scan gives the most accurate date, so go by what your doctor says after the dating ultrasound.
