Researchers at University College in Dublin told New Scientist magazine it is too early to tell if the changes they found in the cells of mice are harmless or what the implications of the findings could be for humans. We now have grounds to question that assumption. During the study, the rate of cell division in mice that were given an 8 megahertz scan lasting 15 minutes was 22 percent lower than normal, and the rate of cell death doubled. Routine hospital scans use frequencies between 3 and 10 megahertz and can last up to 60 minutes. Brennan said the sound waves of the scans could be damaging the DNA in cells, which could delay cell division and repair, or it might be switching on p53, a tumor suppressor gene that controls cell death.
Cancer occurs when damaged cells multiply uncontrollably and form tumors.
Mutations in p53 are the commonest gene abnormalities seen in human cancers. Read the article in New Scientist . A Randomized Controlled Trial . A study of over 1400 women in Perth, Western Australia compared pregnant mothers who had ultrasound only once during gestation with mothers who had five monthly ultrasounds from 18 weeks to 38 weeks. They found significantly higher intrauterine growth restriction in the intensive ultrasound group.