How accurate are dating scans in pregnancy
The dating scan is generally the first ultrasound that every mother-to-be will have.
While many women will have a good idea of when they had their last menstrual period, another portion will be far less certain.
This can be due to a number of factors, including whether the pregnancy was planned or not, and if the mother often has irregular periods.
When you are offered a dating scan and the sonographer gains a picture of the baby’s development, they can use this to accurately calculate the baby’s age based on their size and formation.
If there’s any cause for concern then you may be recommended to have the scan before the 12-week mark, and your midwife will be able to assist you with this.
As the scan is designed to assist the doctors’ understanding of the foetal age and when the baby is due, determining when this early scan takes place is occasionally a matter of estimation.