(also called 'fetal anomaly' or '20 week' scan)
The majority of babies develop normally in the womb but a small percentage are affected by either minor or major problems. Knowledge of such developmental problems can be invaluable in planning the appropriate care for the pregnancy. Equally, the absence of any abnormalities or problems on the scan can be a source of much re-assurance to the expectant parents.
This ultrasound examination serves to perform a full assessment of the baby's development in order to reassure the parents that the organs have formed normally.
This includes an examination of the major organs such as the brain, face, spine, heart, stomach, kidneys, bladder, upper and lower limbs and genitalia (sexing) if requested.The examination is best conducted at between 20 and 24 weeks but can be performed at any stage of pregnancy beyond 18 weeks.
It is recommended by the HeaIth Technology Assessment, an evaluation carried out by the Health Department of the Scottish Executive published in 2004 (www.nhshealthquality.org) that all women be offered a detailed scan. Detailed scans are currently routinely available in some but not all Scottish maternity units.
It is important to understand that it is not possible to diagnose all abnormalities using ultrasound. This is particularly the case for heart and brain abnormalities where only 60% of all abnormalities are detected using ultrasound. Factors which influence the quality of the image obtained are the age of the pregnancy (better at 22 weeks than 18), the position of the baby and the patient's bodyweight (image quality tends to be poorer if the woman is heavy) . If the views are not adequate, this will be explained by the consultant and arrangements made for a repeat examination.
In the unusual situation where an abnormality is found or suspected, the significance of this will be explained and a plan of management discussed.
Still and moving images from the detailed scan are recorded to CD/DVD.
In addition to performing a detailed scan it is also possible to use the new 3/4D technology to obtain further images of your baby. The best quality 3/4D images are obtained between 24 and 30 weeks.