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Oxford University Hospitals NHS Foundation Trust
Women's Services

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Ultrasound and Imaging Services

Important: roadworks starting in January 2018 mean there will be delays when driving to the John Radcliffe Hospital.

Please see 'Car travel and parking' for details.

The Obstetric Ultrasound and Fetal Medicine department offers both a Consultant and Sonographer-led service.

Maternity ultrasound

  • Tel: 01865 221715

The Ultrasound Unit offers the full range of obstetric ultrasound examinations. Our service is delivered on two separate levels of the John Radcliffe Hospital Women's Centre:

  • Obstetric Ultrasound Service

    All routine ultrasound examinations and inpatient scans.
    Level 4, Monday to Friday, 8.00am - 5.00pm.
    Occasionally Saturday mornings 8.00am - 1.00pm.
  • Early Pregnancy Assessment Clinic

    Complications of pregancy before 16 weeks gestation.
    Level 1, Monday to Friday, 8.10am - 12.30pm.

Down's Syndrome screening

All pregnant women are offered screening tests for Down's Syndrome. These tests to not give a definitive answer but tell you whether you are at increased risk of having a baby with Down's Syndrome. For more information please see below.

Contact us

  • Prenatal Diagnosis Unit
    Level 6, Women's Centre
    John Radcliffe Hospital
  • Tel: 01865 22171
  • Annie Roberts
    Screening Co-ordinator
  • Tel: 01865 221087

We are a specialist outpatient referral centre. We run clinics every morning by an appointment system. During these clinics, a variety of services are available including genetic counselling, detailed scanning and diagnostic procedures such as chorionic villus sampling and amniocentesis.

Tests in early pregnancy

Early pregnancy and dating scan

This early ultrasound scan provides important information about the number of babies present and the expected date of delivery. Pregnancy and the fetal heart can be seen from six weeks gestation by vaginal scan and from eight to nine weeks by abdominal scan. Accurate measurements and images are taken of the gestational sac and the 'crown to rump' length of the embryo, to accurately date the pregnancy.

Down's Syndrome

Combined Test

Serum blood screening in early pregnancy is performed alongside nuchal scanning in order to identify high-risk pregnancies.

The test is performed at 11 - 13 weeks and if the results show an increased risk a diagnostic test, such as chorionic villus sampling or amniocentesis is offered.

Quadruple Test

This test is offered to women who are more than 14 weeks pregnant at the time of the scan or in whom it has not been technically possible to obtain the measurements required for the Nuchal scan. The quadruple test is a blood test performed at 15 - 20 weeks of pregnancy. Four biochemical markers in the blood are measured and with the mother's age and weight, are used to calculate the risk of the baby being affected by Down's syndrome. This test is not suitable for multiple pregnancies.

Chorionic villus sampling

A chorionic villus sampling diagnostic test (CVS) is performed at 11 - 14 weeks. Using ultrasound guidance, a sample of tissue is taken from the placenta, either using a needle inserted through the abdominal wall or fine forceps through the cervix. The tissue collected is then tested for chromosomal abnormalities. Initial results are usually available within 2 - 3 working days, with a full report available within 2 - 3 weeks.


An amniocentesis is performed later in pregnancy. Using ultrasound guidance, a sample of amniotic fluid is taken using a needle inserted through the abdominal wall. The fluid collected is then tested for chromosomal abnormalities. Initial results are usually available within 2 - 3 working days, with a full report available within 2 - 3 weeks.

Fetal anatomy scan

Between 19 - 21 weeks the anatomy of the baby is scanned in detail. The careful and accurate measurements made during the scan help to monitor the wellbeing of the baby.

Fetal cardiac scan

Consultation and scanning is available in our Fetal Medicine Unit for specialist scans of the heart and major blood vessels.