Pregnancy ultrasound is a medical technique used to capture images and movements of the fetus in the womb. During the process, a sound pressure which is higher than the upper limit of the human hearing is applied. Most often about 20 kilohertz is used for the medical application. This started off with the 2d scans and later was developed into more specific medical technique called the 4d scan ultrasound.

When reflection signature about the inner medium is recognized through the frequency sounds that has been radiated, this create the images. However, the predecessor of pregnancy ultrasound was first credited to be the 2d scans where a two dimensional image is created. The recent years then showed development in the technology as the 3d scanning was used, where a three-dimensional image is created to represent the fetus and the fetal movements.

Like any other kinds of obstetric ultrasound, 4d scans can be done for the following reasons:

• to know the date the pregnancy (gestational age)
• to be able to confirm fetal viability
• learn the location of fetus, intrauterine vs ectopic
• Check the location of the placenta in relation to the cervix
• Check for the number of fetuses (multiple pregnancy)
• Check for major physical abnormalities.
• Assess fetal growth (for evidence of intrauterine growth restriction (IUGR)
• Check for fetal movement and heartbeat.
• Determine the sex of the baby

Fetal Gender (20+ weeks)

Fetal gender scan is a pregnancy scans made for 20 weeks and above to determine the gender of the fetus. This is meticulously performed ultrasound scan examining each system to identify any problems present. The examination includes brain, spine, face, chest including heart and lungs, the liver, stomach and bowel, kidneys and limbs. (source: pregnancy-and-baby-ultrasoundscan.co.uk)

Nuchal Scan (11-13 weeks)

The nuchal test is a Baby Ultrasound scan focusing on the thickness of skin at the back of the baby's neck. Thickened skin is commonly associated with Downs syndrome and other chromosome abnormalities. (source: pregnancy-and-baby-ultrasoundscan.co.uk)

Cervical Assessment (20-24 weeks)

Ultrasound may help identify women who are likely to miscarry or have a premature labour due to a weak cervix. The weakness is reflected by the shortening of the cervix as measured by ultrasound every 2 or 3 weeks. This examination is usually valuable in women with a history of premature labour or repeated miscarriages after the first trimester, that is, from 13 weeks onwards.

Fetal Wellbeing & Reassurance Scan (22-42 weeks)

Involves assessing the baby's growth by measuring the tummy and head size, the water around the baby, the baby's activity and adequacy of bloodflowing around the baby using Doppler.

3D and 4D baby Scans (24-32 Weeks)

This is made to get a three or four dimensional image of the baby in the womb which may help see the gender or recognize fetal problems like malformation of the hand or the limbs.

4d scans was known lately as a new development in the pregnancy scanning technology. The procedure has the same process of the 3d scans however, the fetal movement is highly recognizable in the process because of the rapid shots which created the four dimensional images.

* Is 4d scans as safe as the traditional 3d and 2d ultrasound?

As have been discussed, 4d scan uses the same technology like that of the 2d and the 3d scans only that the frequency has defined more the movements of the baby in the womb.

* Is there any proof that 4d scanning strengthens the bond between the mother and the baby even before birth?

Though this claim is not defined quantitatively, studies show that mothers who have the 4d scans experience has deep emotional attachment to the baby in the womb as she can see the movement and facial 'gestures" of the baby.

* Why is it 4d scans are special?

Even though the 3d and 4d are almost the same in the procedure, 4d scans is said to make childbirth and pregnancy more blissful and exciting.

*How is 4d scanning being done?

4d scans ultrasound is being done by placing a transducer on the abdomen of the pregnant woman.