What to expect from a nuchal translucency scan for Down syndrome

During the scan, a sonographer uses an abdominal ultrasound to look at the pregnancy and measure the clear space at the back of the baby’s neck. The measurement is considered alongside factors such as gestational age and maternal age, and it may be combined with blood screening.

A result that changes the estimated chance of trisomy 21, also called Down syndrome, is not a diagnosis. Screening can also provide information about some other chromosome conditions and the baby’s early development, although it cannot identify every health problem.

Attend within the timing advised by your maternity team, because the measurement is most useful during a specific early-pregnancy window. Wear clothing that allows access to your abdomen and follow the clinic’s instructions about having a comfortably full bladder if requested.

Ask when the report will be available and how the result will be explained. If screening suggests a higher chance, your clinician may discuss further screening or diagnostic testing. You can take time to consider the options and ask for genetic counselling.

The scan itself is not usually a reason to seek urgent care. Contact your maternity team for heavy bleeding, strong abdominal pain, fluid leakage, fever, or feeling faint during pregnancy. Seek advice if the scan could not be completed or you are unsure which follow-up appointment is needed.

Ask what the measurement means with your dates, whether blood screening is included, and when results are expected. If the result is outside the usual range, ask what screening and diagnostic choices are available and what each can or cannot confirm.