How accurate are early ultrasounds for conception dating
) the fetus is clearly seen on trans-vaginal ultrasound and the heart beat can be seen at this early stage (90 to 110 beats per minute under 6 to 7 weeks, then 110 to 200 beats per minute as the baby matures).
the baby and its heart beat can be detected relatively easily with trans-abdominal and trans-vaginal examination.
Read more See 1 more doctor answer With an LMP of "05/05/18" and an ultrasound on 06/15/18 showing fetus at "5w6d", the probable conception occurred between May 17 and May 21, which allows for the life of viable sperm occurring just prior to ovulation, and the length of time the egg is available for fertilization. Read more Er and ob/gyn are both accurate for gestational age; typically transvaginal is more accurate than transabdominal.
Most dating scans are done with a trans-abdominal transducer and a fullish bladder.
The earlier the ultrasound is done, the more accurate it is at estimating the baby's due date.
Ultrasounds performed during the first 12 weeks of pregnancy are generally within 3 - 5 days of accuracy.
Also the fetus cannot bend and twist too much yet, so the length of the body is fairly constant.
However, the accuracy of the ultrasound examination is always dependent on the skill of the sonographer and the quality of the equipment.
There must be a reason and i would direct you to your OB to confirm why this was done in your situation. Read more Ultrasound done early is much better than LMP dating for the "Expected date of Delivery." Conception is another issue entirely.