Blue Mountains Ultrasound

Ultrasound Studies

Obstetric Dating

Preparation »

Ultrasound is an effective means of assessing the early pregnancy. Ultrasound uses high frequency sound waves to image the developing baby. It is undertaken, to determine the age of the pregnancy, where the mother has experienced pain or vaginal bleeding, or to exclude an ectopic pregnancy.

The dating ultrasound assesses the:

  • location of the gestational sac of the pregnancy
  • presence of the yolk sac
  • presence and the number of an embryos (baby)
  • age of the embryo determined by the crown-rump length
  • heart rate of the embryo
  • presence of corpus luteum
  • presence of a haemorrhage (blood collection).
    • You and your partner or guest will be able to view the entire ultrasound examination on a flat screen monitor. The sonographer will explain what you are seeing as the study progresses and will be happy to answer any questions you may have. At the completion of the study she will provide you with a number of glossy black and white photos of your baby as a memento.

      You will not be required to change for this scan. The sonographer will ask you to lower your pants or skirt a little. The assessment is made through the skin with your bladder full. The bladder forms a window through which gestational sac, uterus and ovaries can be assessed. A clear, warm, gel will be applied to your skin during the examination, this is to enable the ultrasound to penetrate the skin layer.

      If the gestational sac is to small for the embryo to be seen or assessed, the sonographer will offer you a transvaginal ultrasound. This procedure will be clearly explained to you, and as with all ultrasound examinations, you may decline to have this study.

      With the transvaginal ultrasound, you will be asked to totally empty your bladder. Then in the privacy of the examination room, you will remove all clothing below the waste, and lie under the sheet provided on the examination couch. The sonographer will then enter the room, and insert a thin sterile ultrasound probe a short distance into the vagina. The sterile transvaginal probe is covered in a latex condom (or non latex condom for those with a latex allergy) and sterile gel.

      You will feel the probe being inserted and then being moved gently within the vagina to assess the gestational sac, uterus, ovaries and the areas adjacent to these. This normally is not associate with any pain. If you feel discomfort or pain during this examination, please tell the sonographer. You can also stop the examination at any point and the sonographer will immediately remove the probe. Once the examination is complete, the sonographer will remove the probe and leave the room while you dress.

      9 Week Embryo
      9 Week Embryo
      12 Week Embryo
      12 Week Embryo