QUESTIONS ABOUT CREATE's ANTENATAL SCANNING SERVICES

What is Doppler Ultrasound examination?

Doppler is a form of ultrasound which measures the speed of red blood cells moving along blood vessels. It takes tow principle forms:

•    Colour Doppler, where a colour map of blood vessels is shown on a conventional ultrasound image
•    Spectral Doppler, where a tracing of the blood flow is shown on a graph so that the speed of flow can be measured

You do not need a separate examination for Doppler; it is taken at the same time as the usual ultrasound examination.

Why is Doppler Ultrasound useful?

Blood flow is important because it is the method by which oxygen is transported to body organs and therefore improves the function of these organs.

Doppler Ultrasound allows us to measure blood flow to the uterus and to the ovaries. During a women's fertile years there is a fluctuation of blood flow during the menstrual cycle with more blood flow to the uterus in the second half of the cycle to aid implantation of the embryo. An increase in blood flow is also found before ovulation around healthy follicles, which gives an indication of the health of the oocytes (eggs).

After the menopause blood flow to the uterus decreases due to the fall of oestrogen and when this occurs the effectiveness of hormone replacement therapy can be monitored by measuring the increase in blood flow.

Are there abnormalities in blood flow associated to specific conditions?

Yes, in polycystic ovary syndrome there is usually an increase in blood flow in the central part of the ovary (stroma), which reflects the local disturbance in growth hormones. Also the blood flow to the uterus is frequently poor which may explain the high miscarriage rate with this condition.

With uterine fibroids there is usually an increase in blood flow and the higher the flow the greater the chance of fibroids growing. With ovarian cysts, a high internal flow indicates an increased risk of malignancy.

What is 3D/4D Ultrasound Scanning?

In conventional 2D scanning the ultrasound image is made up of a series of thin slices and only one slice can be seen at any one time. Although the image is very informative the picture you see does not look like a baby.

With 3D ultrasound a volume of echoes is taken which can be stored digitally and shaded to produce life like pictures of the foetus. 4D scanning simply means that these life like pictures can be seen to move in real time so the activity of the baby inside your womb can be studied.

What are the advantages of 3D/4D Ultrasound Scanning?

The examination time should be shorter since the baby's anatomy can be studied in any plane from the stored computer image. Some parts of the baby's anatomy can be seen much more clearly than with 2D ultrasound, especially the face, arms, legs, fingers and toes. For example, cleft palate has been shown to be more clearly observed with 3D ultrasound.

In addition, activities of the baby inside the womb can be seen which are difficult or impossible to identify on 2D scanning. For example, with 4D scanning the foetus can now be seen to yawn, cry, swallow, blink and perform intricate finger movements. These activities can be seen even in mid pregnancy although they become more common as pregnancy advances.

Bonding between parents and baby has been shown to be stronger when the 3D image is seen compared to the 2D image because the picture of the baby is more realistic. Improved bonding has been shown to improve the mother's care of herself and therefore her baby.

Will 3D/4D Ultrasound always produce a detailed image?

Usually, but not always. Sometimes if the baby is persistently looking face down (i.e. towards your spine) it may be difficult to see the baby's face. If this happens, a repeat scan in one hour will usually succeed because the baby has turned to a favourable position.

Is 3D/4D Ultrasound Scanning safe?

Over 30 years of extensive study, ultrasound has not been shown to cause any harm to mother or baby – indeed routine scanning of all pregnancies is now normal throughout the whole of Europe.

In 3D/4D scanning exactly the same type and intensity of ultrasound is used as with conventional scanning. In fact, 3D scanning should reduce the exposure time as by storing the data on a computer the baby's anatomy can be examined off line without continual scanning. 4D ultrasound scanning will be similar to a conventional scan in terms of exposure.

What is the best time to have a 3D/4D scan?

Good pictures of your baby can be obtained throughout your pregnancy.

In early pregnancy you will see the whole baby moving its arms and legs but details of the face are indistinct. Later in pregnancy you will see clear images of your baby's features.

Will I also need to have a conventional scan at my own hospital?

It is very important that you go through the hospital routine so that no antenatal test is missed out.

By having a 3D scan however, you will have a professional, detailed scan of the baby's growth and anatomy and this information will be sent to your general practitioner.