In many instances the 20 week morphology ultrasound may be the final scan in your pregnancy, but in some cases follow up ultrasound imaging may be required.
The most common reasons include:
- Growth assessment (if you appear to be having a large or small baby).
- Gestational diabetes.
- High blood pressure.
- Placental position.
- Monitor a multiple pregnancy (twins/triplets).
- Check baby’s position.
- Assessment of blood flow to the baby (Doppler scan).
- Bleeding or fluid loss.
As well as assessing the general wellbeing of the baby, measurements will be taken to look at the baby’s growth, placental position, blood flow to the baby and the amount of fluid that is surrounding the baby.
In most cases the ultrasound will be performed transabdominally but there are some situations where an internal or transvaginal ultrasound may be necessary. Transvaginal ultrasound involves placing a thin transducer (slightly thicker than a tampon) into the vagina. The transvaginal ultrasound can offer extra detail to the examination as it allows the ultrasound probe to come into close proximity to the uterus. A transvaginal scan is optional for all patients and it is your decision whether to proceed with that part of the examination.
Transabdominal and transvaginal ultrasound examinations are a safe investigation at all stages of pregnancy.
Before your Scan
It is a good idea to wear comfortable, loose fitting clothing that allows easy access to the area that is being imaged, so two piece clothing is ideal (separate upper/lower garments).
Transabdominal: Drink 500mL of water finishing one hour prior to your appointment and do not empty your bladder. Your bladder need not be overly full that it causes you pain or distress; please advise reception staff on arrival if this is the case and you will be advised of your options. If during the examination your bladder is causing you discomfort, please advise the sonographer.
Transvaginal: If this imaging is required it is performed with an empty bladder.
Preparation details for your examination will be confirmed when you make your appointment.
Approximately 30 minutes.