Contact us 0345 602 8179

From screening for Down Syndrome and examining the baby for normal development, through to sexing the baby, estimating the baby's size and providing images, modern ultrasound equipment and technical expertise enables women to avail themselves of a full pregnancy scan service. There are several types of pregnancy scans.

Early pregnancy scans

These scans are performed for several reasons. The principal reason is for reassurance that the pregnancy is progressing satisfactorily and that the baby's heartbeat is present. The age of the pregnancy is easily determined through ultrasound measurement and the presence of one, two or more babies is established.

The examination is usually carried out by scanning through the abdomen but if the pregnancy is very early, scanning via a probe inserted into the vagina may be appropriate (transvaginal ultrasound).This scan is of value to any woman who may have concerns about her pregnancy, who is unsure of how far along she is or simply wishes to see the pregnancy progressing.

Nuchal scan - The combined ultrasound and biochemistry scan (CUBS)

This assessment is for women who wish to have a screening test for the prediction of a baby with Down's Syndrome. The test combines the woman's age, the measurement of 2 proteins (biochemical markers) in the mother's blood and a measurement of the skinfold behind the baby's neck at 11.5 to 14 weeks of pregnancy. A new development in first trimester screening is the assessment of the nasal bone. If you are expecting twins then the Down's risk is calculated from the nuchal ultrasound measurement and the mother's age alone.

What is the CUBS test?

The CUBS (combined ultrasound and biochemistry scan) test best performed between 11 and a half and 14 weeks. The scan is similar to the first 'booking' or early pregnancy scan but may take 20-30 minutes because of the additional detail required to make the measurements. The scan is usually best performed with an empty bladder as the consultant may need to press firmly on the abdomen to get the best views of the baby's neck.

The fetal nasal bone can be visualized by sonography at 11-13+6 weeks of gestation. Several studies have demonstrated a high association between absent nasal bone at 11–13+6 weeks and trisomy 21, as well as other chromosomal abnormalities.

The results of the first 6000 screening CUBS tests revealed that the test has a greater than 90% detection rate for Down's syndrome which is appreciably better (more accurate) than the routinely available blood test offered at 15 to 20 weeks.

The blood sample will be taken by one of the clinic staff and women will be informed of their results by telephone after 2-4 days. A written report is posted to your address.

The result of the screening test is reported in two ways. Firstly, the result is categorised into a 'low risk' or a 'high risk' result. The cut-off for determining the two risk categories is 1 in 250. Ninety-five percent of women will have a 'low risk' result and no further action is usually recommended. The actual risk of Down's syndrome is also provided; the lowest risk that can be quoted is less than 1 in 20,000 whilst the highest is greater than 1 in 2.

Should a high risk of Down's syndrome be received, your consultant will discuss the implication of the result with you.

The integrated test

There is high-quality evidence to indicate that combining results of first and second trimester screening tests improves the diagnostic performance for Down’s syndrome and other chromosomal anomalies and is better than when either of them is used alone.The test  is a 2 stage procedure incorporating the Nuchal scan as outlined above followed by the blood test performed at 15 weeks. The results are available after 15 weeks.

Detailed scan (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.

Growth and wellbeing scan

This examination is normally performed later in pregnancy (> 26 weeks) when a woman wishes to have the baby's size estimated. This scan concentrates on performing measurements of the head, waist, and thigh bone. It is possible to estimate the baby's weight using these measurements.

The baby's wellbeing is assessed by examining the amount of fluid around the baby and the function of he placenta ('afterbirth') using a technique called Doppler Ultrasound. Doppler measures the pattern blood flow in the baby's umbilical cord. 

It is not necessary to be referred for an ultrasound scan with most women booking their scan directly. Each scan is accompanied by digital images of the scan (on CD or DVD as appropriate) and a written report provided.

Find your nearest hospital that provides this test

Cardiff Bay Hospital
Dunleavey Drive
CF11 0SN

02920 836700

25 Beaconsfield Road
G12 0PJ

Contact us 0345 602 8179

Get in touch

Fill in an enquiry form below or call us

Thank you for your enquiry. A member of the team will respond to you soon.

Pregnancy nutrition

Good pregnancy nutrition | A trimester-by-trimester guide

If you’re expecting a bundle of joy and are unsure about your diet, read on – Nutritional Therapist Tracey Strudwick guides you through nine months of optimum eating for you and your developing baby.

Read full article