Understanding Your Pregnancy Timeline: Reconciling Scan Dates and Conception

Question
Went for a scan 13 march 08 and was told i was 6weeks 5days.
had another scan on 10 april 08 as i was having cramping and it measured at being 10weeks 4days.
All scans date back to 26th jan 08 (give or take a couple days), but my lmp was 30th jan 08.
Not sure on my cycle as only came off the pill in november but roughly when was conception.
Could i have conceived dec 07?? but that would make scan dates wrong by 5-7 weeks.

Answer
Tina,

No, that's not possible.  Early ultrasound is the most accurate method to determine fetal age and is typically off by less than 3 days in either direction.

Based on your ultrasound results, you most likely conceived around Feb. 9, 2008.


Best,
Catherine