One of the greatest boon that technology has contributed to modern medical science is Ultrasonography or Ultrasound scans. Each and every detail of the human body whether it is a small scar or a big tumor can easily be detected using this technique. Even though a Ultrasound scan is widely used to detect a variety of medical complications, it is more prevalent in the world of Obstetrics and Gynecology.

What is  an Ultrasound Scan?

An Ultrasound scan is high frequency sound waves that are sent through your body to detect any growth within the body. The person who does an ultrasound scan is called a Sonographer. In case of pregnancy, this sound wave is sent through your womb or uterus to detect the position of the fetus. These sound waves bounce the fetus as an echo which is later turned into an image on a screen.  The hard tissues of the body like bones reflect the highest echo and it appears white in color in the image. Soft tissue appear grey in color and fluids appear black in color.

What normally happens during an Ultrasound scan?

The expectant mother who is undergoing the scan is asked to keep her bladder full. This provides a better picture of the fetus. The mother is then asked to lie on the back and a lubricating gel is applied onto the abdominal area. A small device is then moved forward and backward on the abdomen to detect the fetus. Once detected the image appears on the screen. For a layman,  the image might appear vague. You can seek the help of your sonographer to decipher the image.

What does the Ultrasound scan reveal?

Even though there is no hard and fast rule regarding the number of scans that can be performed during pregnancy, generally it is done three times for a normal pregnancy. The first scan is done between 10-12 weeks, second scan between 18-20 weeks and third scan between 32 – 36 weeks. But if the maternal age is more than 35 or if the mother is carrying twins, then more than three scans may be prescribed. Depending on the gestational age of pregnancy the scan reveals the following

Scan during first trimester:

First trimester scan reveals:

  • Position of baby in the uterus

  • Number of babies you are carrying

  • Heart beat of the fetus

  • Length of the fetus

  • The due date

  • Risk of Down Syndrome or any chromosomal abnormalities

Scan during Second trimester:

The second trimester scan throws light on

  • Whether the fetus is growing as per pregnancy milestones

  • Whether all the internal organs are developing well

  • Whether the placenta is in the right position

Scan during Third trimester:

The third trimester scan provides a good picture of

  • The position of the fetus ie whether normal or breech

  • The position of the umbilical cord, whether it is around the fetus’s neck

  • The amount of amniotic fluid

  • The baby’s head and abdominal circumference

  • Weight of the baby

One of the major concerns with respect to ultrasound scan is whether it is safe during pregnancy. Ultrasound scans have been carried out in pregnant women for decades and no adverse effects were reported until now. Hence it is presumed to be safe both for the mother and baby.

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