Find out what happens at your 1st NHS ultrasound pregnancy scan, why it's called a dating scan and whether you find out your baby's sex. Find out more about your 12 week dating scan. What it involves, why it's important to have it and where you'll have the scan. The 7 weeks ultrasound is a special time as this is when the heartbeat can be detected. This is a scan or ultrasound which determines your expected date of.
By 6 to 7 weeks gestation the fetus is clearly seen on trans-vaginal ultrasound and the heart beat can be seen at this early stage 90 to beats per minute under 6 to 7 weeks, then to beats per minute as the baby matures. Ultrasounds performed during the first 12 weeks of pregnancy are generally within 3 - 5 days of accuracy. The most accurate time is between 8 and 11 weeks gestation. This is because the fetus is growing so quickly that there is a big difference in size from week to week.
The scan or my dates - which should I believe? The EDD from the early dating scan is used - if the last menstrual period is not known or is unreliable, or the what week dating scan scan differs from the last menstrual period dating by more than 5 days. Ultrasound examinations from 12 to 22 weeks are regarded as being within 10 days of accuracy or up to 10 days earlier or 10 days later than the woman's calculated due date.
Ultrasounds performed after 22 weeks gestation cannot be used to estimate the due date of the baby because the size no longer reflects the age very well. Even average babies can differ by up to 2 to 3 "weeks of growth".
Ultrasound of Normal and Abnormal early pregnancy
Hello everyone! It's the last pregnancy video before I'm all caught-up, so if you want to see how I am feeling right now, my 14 week update is going live.