Obstetric Ultrasound

PREGNANCY ULTRASOUND

Question 1. What is ultrasound scanning?

Ultrasound scanning is a procedure that uses high-frequency sound waves and their echoes to create video pictures of organs in the body. It is a very safe test that will not hurt you or the baby.

 Question 2. When is it used in pregnancy?

Your healthcare provider uses ultrasound scanning to examine your unborn baby. He or she also uses it to look at your uterus, amniotic sac, placenta, and ovaries.

Ideally, pregnant women should have one or more ultrasound scans as part of their routine antenatal care when available. You are more likely to need ultrasound scans if your healthcare provider thinks there may be a problem with the pregnancy or if you have risk factors that could lead to problems for the baby. Ultrasound scanning is very helpful for many abnormal conditions.

Some of the reasons ultrasound scanning may be done during pregnancy are to:

Make sure the baby is developing in the uterus and not in a fallopian tube (ectopic pregnancy).

See how far along you are in your pregnancy and establish your expected date of birth of baby

Check the age, size, weight, and position of the baby.

See if the placenta is normal and attached properly.

Check for any problems with the uterus.

See if the baby's body has any major problems.

Check the amount of fluid around the baby inside the uterus.

Check for more than 1 baby.

Check the baby's heart.

Look for movement by the baby and breathing movements of the baby's chest.

Help with an amniocentesis or other tests or procedures.

Check the baby for signs of stress as part of a biophysical profile.

Check into the cause of vaginal bleeding or pelvic pain.

Question 3. When is the best time for ultrasound scanning in Pregnancy?

An ultrasound scan may be done for different reasons at different stages in the pregnancy. For example, tests to see if the baby is growing at a normal rate are most accurate during the second trimester of pregnancy. To check the age of the baby or check for more than 1 baby, an ultrasound is often done between the 16th and 20th weeks of pregnancy. Sometimes a baby's gender may be learned by looking for the genitals in an ultrasound scan after the 16th week of pregnancy. However, this is not usually a reason for doing an ultrasound.

Your doctor will advise the best time for your ultrasound depending on your individual circumstances and reasons for doing the scan.

 Question 4. How do I prepare for ultrasound scanning?

If your bladder is full, it may be easier for your healthcare provider to see the baby and other organs. For this reason your provider may ask you to drink up to 6 glasses of water 1 hour before the test and then not to urinate until after the test. Your provider will tell you if this or other preparations are needed.

 Question 5. What happens during the procedure?

The ultrasound scan may be done at your provider's office, at a clinic or hospital, or at a radiology centre. A small device called a transducer is used to do the scan. The transducer acts like a microphone. During the scan, high-frequency sound waves enter your body through the transducer. The transducer is connected to a computer. As the sound waves pass through your body, they are reflected back to the transducer by the organs. The computer analyses these echoes and produces images of the organs on a screen.

The ultrasound exam is done by putting the transducer on the surface of your abdomen. First your provider or the ultrasound technologist will put oil or gel on the skin of your abdomen. This helps the transducer glide smoothly over your skin and improves its contact with your body enable better quality images. Your provider will move the transducer over different parts of your abdomen to get pictures of the baby and the uterus.

Some ultrasound exams, especially early in pregnancy, are done through the vagina. For these scans the transducer is shaped like a narrow tube and covered with a condom like sheath. It is inserted gently into the vagina. An ultrasound scan takes about 15 to 30 minutes. You can watch the images of your baby on the screen while the scan is being done.

 Question 6. What happens after the procedure?

Usually you can go home and go back to your normal activities as soon as the scan is done. You may be able to have the results within a few minutes to a few days later.

 Question 7. What are the benefits of this procedure?

Ultrasound scans can improve a baby's chances of health and survival by:

detecting possible problems that might be corrected before the baby is born

providing more accurate information about the baby's health before birth

Preventing premature birth with a more accurate determination of the due date.

There are no known side effects from ultrasound scanning. In addition, no medicines are known to interfere with test results. Ultrasound scanning is fast and painless. It does not use radiation and avoids possible hazards of some other tests used for diagnosis, such as bleeding, infection, or reactions to chemicals.

 Question 8. What are the risks of this procedure?

There are no known risks associated with ultrasound scanning because the sound waves used are not dangerous. However, if it is necessary to use anaesthesia or to insert a medical instrument into the body to conduct the ultrasound, there may be a slight risk associated with the procedure.

 Question 9. Where can I have the procedure?

Enquire with your local clinic or doctor to see if their centre or hospital does ultrasound in pregnancy. Major public hospitals in PNG would offer ultrasound services under standard procedure. Ultrasound can be easily performed through a private practice in Port Moresby or Lae but off-course with a cost.

  Question 10. Can I have an ultrasound at 6 weeks?

At 5-6 weeks gestation, a small gestation (pregnancy) sac is seen within the uterus. A Transvaginal ultrasound is usually required to see the baby at this stage of the pregnancy. You should not be concerned if we cannot see the baby's heartbeat at this early stage, as this can be normal.