Are ultrasounds safe during pregnancy?
Pregnancy is the most important phase of a woman’s life. While the blissful period gives you a reason to cheer, the thoughts of having a healthy baby bring jitters.
Ultrasound scans thus come across as a handy tool that keeps the nervous mums-to-be updated about her child’s health and well being.
Depending upon the stage of pregnancy at which an ultrasound is done, it provides valuable insights about the baby’s health and growth.
While early pregnancy scan aid in confirming pregnancy and due date, second trimester scans are conducted to pick up anomalies in the fetus, if any.
Ultrasounds performed in the third trimester are referred to as the ‘growth scans’. They help the obstetricians know about the baby weight and the position of the fetus.
Are scans harmful?
Unlike x-rays, ultrasound scans use high-frequency sound waves. These inaudible sound waves are transmitted through the uterus which bounce back from the baby. The echoes are transformed and recorded as an image on a computer screen.
The sonographer can pick up details of amniotic sac, placenta, and ovaries and check for major abnormalities like birth defects.
While the benefits of undergoing ultrasound scans during pregnancy are well pronounced, excessive use of such scans can have harmful effects, researchers say.
Previous studies have established two potentially harmful effects of excessive scanning:
Cavitation is a condition wherein small air bubbles develop in the body. However, cavitation is not possible during pregnancy scanning as there is no air present in the womb.
Heating: As the ultrasound waves penetrate through the skin they increase the temperature of the tissues. A significant rise in the tissue temperature may cause harmful effects.
But as normal pregnancy scans are based on 2-D screening, they produce very little heat and are thus safe for the baby. Moreover, regular movements of the baby and the protective fluid around the fetus help distribute the heat, lowering adverse outcomes.
However, Doppler scans and colour scans produce more heat than the 2-D scans. This is because they work by concentrating a beam of sound in a small area, raising tissue temperature significantly. But latest scan machines automatically lower the strength of the ultrasound beam, cutting its intensity. This mechanism lowers the adverse outcomes of using a Doppler or coloured scan.
We at ‘themedguru’ advise that every expecting mother should go in for the recommended scans without worrying about its effects on her unborn baby. However, excessive ultrasound screening should be justified and restricted to the minimum required for making a diagnosis.
Edited by: Medhavi Gulati