Ultrasound or sonogram is a method that uses sound waves to study the internal parts of a human body. It is widely used in all branches of medicine, especially in obstetrics and gynaecology. Undergoing an Ultrasound scan is a special part of a pregnancy, as you get to see your baby for the first time in the visual image created by an ultrasound. This imaging technique helps the doctor to evaluate various aspects of a pregnancy, including detection of birth defects and determination of the well-being of the unborn baby.
When are ultrasound scans done?
Usually, three ultrasound scans are recommended in a healthy pregnancy. However, when there are high risks factors/complicated pregnancies, more scans are required.
Your doctor will determine when you need an ultrasound. Make sure to have your prenatal check-ups regularly even though you have done the routine ultrasounds.
Ultrasounds during the first trimester
During the first trimester i.e., 6 to 14 weeks, ultrasounds may be performed to:
- Confirm the pregnancy
- Check the heartbeat of the fetus
- Check for twins or multiple pregnancies
- Examine the ovaries, uterus, placenta and cervix
- Diagnose an ectopic pregnancy
- Determine the gestational age of the fetus and estimate a due date for delivery
Ultrasound scans during the second and third trimesters
During the second trimester i.e., 14 to 24 weeks and third trimester i.e., 24 to 37 weeks or birth, ultrasounds may be done to:
- Monitor the growth of the fetus
- Make sure the position of the fetus is normal
- Examine the placenta to check for problems such as placental abruption and placenta previa.
- Look for birth defects or congenital abnormalities
- Check for structural abnormalities
- Check if the fetus is getting enough oxygen
- Monitor the amniotic fluid level
- Diagnose problems with the uterus
- Measure the length of the cervix
- Guide other tests like amniocentesis
Does ultrasound pose any risk?
Ultrasound can be safely performed and does not pose any risk to the mother and the baby. As sound waves are used instead of radiation, ultrasound is safer than an X-ray. Ultrasound during pregnancy is considered a normal part of prenatal care.
What preparation is required for an ultrasound scan?
There is no need of any special preparation to undergo an ultrasound. Sometimes the pregnant woman may be asked to drink around six glasses of water before the commencement of the ultrasound and avoid urinating until the ultrasound is done. It is easier for the doctor to view the fetus and its organs when the urinary bladder is full. This request is ONLY for early pregnancy scan. There is no need to fast for pregnancy scan. Expectant mums can have a normal diet.