Ultrasound is a routine part of the prenatal care enabling obstetricians and pregnant women to monitor the development of the unborn baby from as early as 5 weeks gestation.
Ultrasound is being used not only to evaluate the normal development of the baby but also to identify the sex and provide 3D and 4D images something that became possible following advances in the development of ultrasound equipment.
Early pregnancy scans
In early pregnancy, ultrasound is being used to reassurance that the pregnancy is progressing satisfactorily and that the baby's heartbeat is present. For mother with irregular periods, ultrasound is being used to date the pregnancy through ultrasound measurements.
This early pregnancy scan is of great value to any mother who may have concerns about the health of their baby, who is unsure of how far along she is or simply wishes to see the pregnancy progressing. It can help reduce anxiety.
Other scans throughout the pregnancy are the:
The detailed or 20-week scan
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.
Limitations of baby scans
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 body weight (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.
3D and 4D ultrasound scans
Using new ultrasound technology it is possible to obtain lifelike images of the unborn baby in 3 and 4 dimensions (4D is moving 3D). Such images are very popular with parents since they provide easily recognisable images of their baby’s face in particular which they can share with family and friends. Smiling, yawning and sucking is often seen depending on how awake or asleep the baby is.
The quality (how clear they are) of the 3/4D images is mostly determined by the baby’s position and how far along the pregnancy is. The best time to do a 3/4D scan is between 26 and 32weeks. It is difficult to influence the baby’s position but time is set aside to allow the baby to wake and move around if necessary. If it is not possible to obtain satisfactory images (which is very unusual) for whatever reason then we will make arrangements for a further scan or adjust the charge depending on your preference.