Ultrasound Scan : Its Necessity and Benefits in Pregnancy : An ultrasound scan is the picture of the baby and her surroundings. In an ultrasound scan, high frequency sound waves (3.5 7 MHz) are sent through the layers of the abdomen into the uterus. The baby reflects back the sound waves. A computer captures and translates these echoes into an image. The rate of reflected waves gives various colours from black to white to the picture.
Ultrasound scan shows your baby’s position and its surrounding – Hard tissues such as bones show up as white areas on the image, and soft tissues appear grey and speckled. Fluids, such as the amniotic fluid, do not reflect any echoes, so appear black. These different shades of white, grey and black help the doctor to interpret the images. The images show the baby’s position and movements as well as the well being of her surroundings. The technical advances have facilitated the development of 3D and 4D coloured scans as well. These give more pronounced images of your baby.
The procedure for ultrasound scan is simple – Your doctor asks you to come with a full bladder for the procedure. You may feel some discomfort from pressure on the full bladder, but it helps to conduct sound waves more efficiently. The conducting gel applied over your abdomen is non-staining but may feel slightly cold and wet. There is no sensation at all from the ultrasound waves.
Ultrasound scan is absolutely safe – Unlike X-rays, the ultrasound does not use any electrically charged ions for the scan. Hence, chances of any adverse effect due to irradiation are inapplicable. But if it is done by inadequately trained medical staff or by using poor equipment then there is a chance of over or under diagnosis.
Ultrasound scan and its importance in healthy pregnancy – Diagnosis and confirmation of pregnancy Ultrasound scans can visualize gestational sac, yolk sac and embryo as early as 4 to 5 weeks of gestation. It can also find out the site of implantation of the embryo and can also help to diagnose ectopic pregnancy.
Identification of causes for vaginal bleeding – It can very well detect the causes of vaginal bleeding in early pregnancy by the shape and size of the gestational sac and placenta. Missed abortions and blighted ovum usually show deformed gestational sac and absence of heart beat. Ultrasound scan is indispensable to identify ectopic and pregnancies if there is bleeding in the first trimester.
Determination of gestational age and foetal size – In early pregnancy, the measurement of the body of the foetus is usually done with the help of ultrasound. It also reflects the gestational age of the foetus.
Diagnosis of foetal abnormalities – Many structural abnormalities of the foetus, like Spina Bifida and Down’s syndrome can be reliably diagnosed by an ultrasound scan even before 20 weeks of gestational age.
Determining placental location – It is vital in locating the site of the placenta and determining its lower edges, thus making a diagnosis or an exclusion of placenta previa.
Multiple pregnancies – Ultrasound is invaluable in determining the number of foetuses in Case of multiple pregnancies. It also shows presentation, growth, retardation, anomaly and presence of placenta previa of the foetus. It is also capable of suggesting twin-to-twin transfusion in case of multiple pregnancies.
Determining the growth of the foetus – Ultrasound plays a significant role in determining your baby’s heartbeat, movement, tone and breathing.
Diagnosis of pelvic abnormalities – It also helps in the diagnosis of uterine and pelvic abnormalities during pregnancy e.g. fibromyomata and ovarian cysts.
Ask your doctor for the dates
There is no hard and fast rule as to when you must get your ultrasound done. Your doctor is going to suggest you to get the ultrasound done whenever the need to look into the intrauterine health more closely is felt, depending upon the health of the mother. But generally, the first scan is done at 7-8 weeks of gestation, the second at 11-13 weeks, third at 18-20 weeks, fourth at 30 weeks and a final scan at 36-37 weeks of gestational age. Ultrasound scan is important to understand the position, growth and movement of your baby. Consult your doctor for advice regarding the need of an ultrasound scan.
Note: Any medical information published on this website is not intended as a substitute for informed medical advice and you should not take any action before consulting with a healthcare professional.