Scan tests are performed to ensure the healthy growth of the baby. During low risk normal pregnancy, 3 scans are performed:

1. Viability Scan – This is the first scan performed between weeks 6 and 9 to confirm the pregnancy date and arrive at an estimated due date. This scan is also used to confirm the location of the fetus, presence of fetal heart activity and the number of babies (singleton/multiple).

2. Nuchal Scan (NT) – Usually, the NT scan is performed between weeks 11 and 14 to check for any developmental problems or chromosomal abnormalities like Down syndrome in the fetus. This scan will ensure the normal body development of the baby.

3. Routine Anomaly Scan – The third scan is performed around 18 to 23 weeks of pregnancy to check the growth of heart,kidneys, brain and facial features. It will detect any major or minor anomaly in the development of the fetus.

Apart from these, if it is a risky pregnancy, the gynecologist might want to go for further scans to check the well being of the baby inside the womb.

4. 4D Ultrasound Scans: A New Trend in Pregnancy Care Having an ultrasound scan during pregnancy is a part of prenatal care to check the growth and normal development of the baby inside the womb. These scans can detect any developmental abnormality in the baby so that necessary actions can be performed. Apart from diagnosis, ultrasound scans are also used the see the baby before its arrival. 4D ultrasound scan shows a clear video of the baby moving inside the uterus which can be made into a DVD. 

A 4D ultrasound scan is the moving 3D images of the baby inside the uterus, having time as the fourth dimension. It clearly shows the movements and the facial features of the baby in real time like a video. The difference between 2D, 3D and 4D scan lies mostly in the computer software advancement rather than the scanning mechanism. The 2D scan can show the baby’s internal organ while the 3D and 4D scan shows only the external features. The 2D scan has grey blurry lines that show the baby’s movement while 3D scan shows clear images of the baby like a photo. The 4D scan on the other hand shows clear movements of the baby where one can seethe facial expressions, body movements, shape of the nose, mouth, eyes etc.

When is the right time to have a 4D scan? It is advisable to wait for 28 to 32 weeks in order to have a clear 4D scan result. However, it is important to consult your doctor about the scan, its advantages and disadvantages before making a decision.