Start Obstetric dating scan

Obstetric dating scan

You’ll be asked to lie down on a table and required to expose your abdomen, down to the pelvic bone, but you can keep your underwear on.

Ultrasound is used to take a measurement of a particular skin fold at the back of your baby’s neck.

In babies with Downs syndrome, this fold of skin is thicker than in babies without the syndrome.

This helps the scanning head to glide smoothly over your skin to get a clear image.

Most dating scans are done with a trans-abdominal transducer and require a full bladder.

However, if the pregnancy is in very early stages, the gestational sac and foetus may not be big enough to visualise and you may be offered an internal, transvaginal (TV) scan which will result in clearer images.

Sometime between weeks 12 and 14 of your pregnancy you might be offered a Nuchal translucency scan.

Wear comfortable clothing, including a two piece garment.

This measurement is used, along with the results of blood tests, to calculate the your babies risk factor.

You should arrive 10 minutes before your appointment time to complete all necessary paperwork.

The main purpose of an early obstetric/dating scan ultrasound’s is to determine the viability of your pregnancy, to confirm how many weeks pregnant you are and to estimate your due date.

This scan will also show if you are expecting a multiple pregnancy.