Dating Scan

A pregnancy dating scan, also known as an early pregnancy or viability scan, is an ultrasound procedure typically conducted between 7 to 10 weeks of gestation. A dating scan is conducted to achieve the following objectives:

Confirming A Pregnancy

The pregnancy dating scan is one of the first steps towards confirming a pregnancy. Here’s how a dating scan confirms a pregnancy:

Visualising the Gestational Sac: The first sign of pregnancy on ultrasound is the presence of a gestational sac, a small fluid-filled sac that houses the embryo, in the uterus. It can usually be detected by around 5 weeks of gestation.
Identifying the Yolk Sac: Within the gestational sac, the yolk sac can be identified. The presence of a yolk sac helps identify the gestational sac at this early stage of pregnancy.
Detecting the Embryo: The embryo itself can usually be visualised after 6 weeks of gestation.
Visualising the Heartbeat: One of the most significant markers of a viable pregnancy is the detection of the baby’s heartbeat, which can be seen through an ultrasound scan from around 6-7 weeks.

Calculating A Due Date

One of the main purposes of the pregnancy dating scan is to calculate or confirm a pregancy’s expected due date. The EDD from the last menstrual period (LMP) is calculated under the assumption of a regular 28 day menstrual cycle. In the event of irregular menstrual cycles or a shorter/longer cycle, EDD may differ from what is calculated by general dating apps or calculators.

Here’s how a dating scan calculates a due date:

Crown-Rump Length (CRL) Is Measured: The length of the embryo or fetus from the top of the head (crown) to its bottom (rump) is measured.

Early dating assessment of an 8 week fetus by measurement of Crown-Rump Length (CRL)

Gestational Age Is Calculated: Once the CRL is measured, it is compared to a chart or a formula that provides the average CRL for each week of pregnancy. This comparison allows the ultrasound specialist or doctor to estimate the gestational age of the pregnancy.

According to the Australasian Society of Ultrasound in Medicine (ASUM) Guideline for the performance of First Trimester Ultrasound, the EDD by LMP (adjusted for cycle length) should be used unless the LMP is unknown or if the gestational age by the CRL differs significantly or by more than 5 days.

EDD by assisted reproduction dates (for example, IVF) should only be adjusted with extreme caution.

https://www.asum.com.au/files/public/SoP/curver/Obs-Gynae/Guidelines-for-the-Performance-of-First-Trimester-Ultrasound.pdf

Identifying Multiple Pregnancies

During a dating scan, we also determine how many babies are present. This is important as multiple pregnancies require more careful monitoring throughout the gestational period.

Detecting Early Concerns

A pregnancy dating scan can detect early concerns, such as an ectopic pregnancy or signs of miscarriage. Detecting and addressing these concerns at an early stage can be crucial for the health and wellbeing of both baby and mother.

We are here for you

At QUFW, our team of women’s health doctors, sonographers and healthcare professionals is dedicated to delivering exceptional care in a relaxing and supportive environment. We welcome you to schedule your dating scan with us, and become a part of the community of women who have trusted us with their prenatal care. For more information or to schedule an appointment, please get in touch with us today.

Appointment Enquiry

8 week fetus with heartbeat

3D image of an 8 week fetus

about QUFW

QUFW provides a comprehensive range of obstetrics services for singleton and multiple pregnancies, including screening, tertiary opinion and invasive testing. In addition, our gynaecology ultrasound examinations are equally expansive from routine to gynaecology procedures.

Beyond your scan, we believe in comprehensive care. Our team takes the time to discuss findings with you, answering your questions, addressing your concerns, and providing you with support and guidance. We value the trust placed in us and are committed to delivering ultrasound and other women’s health services to our community and beyond. We are QUFW. We are here for you.

FREQUENTLY ASKED QUESTIONS

What are your opening hours?

Our Brisbane practice is open Monday – Friday 8am to 5pm, Saturday 8am-12:30pm.
Our Ipswich, Southport and Tugun practices are open between Monday – Friday 8am to 5pm.

Where can I park my car?

Spring Hill: Metered street parking on Little Edward and Boundary Streets (Please be aware of the clearway zone at certain times of the day).

Parking underneath the Leichhardt Court building (orange section) with entry via Hope Street. Online bookings are recommended through Wilson parking.

Southport: 4 hour metered parking is available on Short Street. Additional car parking available in the Gold Coast City Council Carey Carpark and Australia Fair Shopping Centre

Ipswich: Onsite Parking is available at the back of the Medical Centre. Metered on street Ipswich City council parking is also available.

Tugun: Onsite car parking is available in the John Flynn Hospital campus.

How much will my scan cost?

The cost of the ultrasound and consultation will be discussed at the time of making an appointment. We request that accounts be settled on the day after the consultation. We have EFTPOS and accept MasterCard, VISA and American Express. We are a private medical ultrasound service and we do not routinely bulk bill as this would not allow us to provide the best comprehensive service for our patients.

How long will the appointment take?

Our scans can range from approximately 30-60 minutes depending on the type of scan, but please allow up to 90 minutes. Occasionally there are unexpected delays. If a problem is detected in a routine ultrasound, it will be discussed with you at the time of your appointment. In this situation, further examination and reassessment may extend over a longer period depending on the complexity of this problem and individual patient needs. This process may lead to delay of the assessment of other women’s appointments.

We apologise for these delays which are unpredictable and we make every effort to avoid significant patient inconvenience. We ask that you demonstrate kindness to our staff if there is an unforeseen delay. We recommend that you ring our rooms in advance to check that we are not significantly delayed so you can plan your day and parking arrangements.

Can I bring another person to my appointment?

At QUFW, we allow two support people to attend your appointment. One of these support people may be a child. Sometimes pregnancy ultrasounds can be a long time for your little one’s attention span, so we request that the other support person is a supervising adult who may be able to attend to your child during the scan if necessary. If you are a surrogate patient, we are happy to discuss this with you when you make your appointment.

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