Baby dating ultrasound
Speak to your doctor if there are things you don't understand or if you have any concerns after the scan.
There are two ways of doing a first trimester scan: Transvaginal scan (TVS) If your doctor wants you to have a scan earlier than 10 weeks of pregnancy, you will have a transvaginal scan.
It is offered when you are around 11 to 14 weeks pregnant.
In some areas the dating scan and the NT scan will be carried out together.
In these early weeks of pregnancy, your baby is too small and low in your abdomen to be picked up by an abdominal ultrasound scan.
A vaginal scan is done by introducing a probe into your vagina. Abdominal scan After 10 weeks and for the rest of your pregnancy, you will have an abdominal scan.
Drink 0.5 Ltr (1 pint) clear fluid approx 1 hour before appointment time.
Please do not empty your bladder before the examination.
In practice, you may find that the timing varies across the country.The first is known as the ‘dating scan’ because it helps to show how many weeks pregnant you are, it can also check your baby's development.Additionally you may be offered a special ultrasound called a ‘nuchal translucency scan’ (NT) which in combination with a blood test is used to screen for Down’s syndrome.You can calculate your due date by subtracting three months from the first day of your last menstrual period (LMP) and then add a week. A pregnancy is based on being 280 days long, which is 40 weeks (more like 10 months not 9! When we give you a due date we consider 37 to 42 weeks to be full-term, so even if your baby is born two weeks before your due date it is not considered premature.The accuracy of using your LMP to date your pregnancy depends on having regular cycles and assumes you ovulated (released an egg) on day 14 of your cycle and conceived right away - none of which may be true.
We recommend that you present your dating scan results to your usual healthcare professional whose contact details we take at the time of booking.