Beverley Beech and Jean Robinson have written this week to Matt Hancock, the Health Minister, about the routine use of ultrasound in pregnancy. Women are being warned not to buy and use the means of conducting their own investigation of their unborn baby on the grounds that they have not been specially trained to read the results. They are not being told that ultrasound has never been properly tested on developing human beings although there are studies showing damage to animals. Here is their letter in full. It marks the beginning of a campaign to make sure that women are fully informed about possible dangers before they accept ultrasound screening.
Current advice to women is that since alcohol in large quantities clearly damages babies in the womb, the only safe strategy is total abstinence. Ultrasound at high levels has been shown to damage growing brains, maybe we should adopt a cautious strategy here too.
We are writing to draw your attention to research concerning ultrasound safety conducted by Chinese researchers and reviewed by Jim West in his Bibliography ’50 Human Studies indicate Extreme Risk Prenatal Ultrasound a New Bibliography’.
In October 1982 Jean Robinson and I wrote to the then Minister of Health – Dr Gerard Vaughan – telling him of our concern about the widespread use of ultrasound before it had been evaluated. To our astonishment he replied that the Medical Research Council had considered the possibility of a trial to assess potential benefits and hazards of using ultrasound in pregnancy in 1976 and had rejected it stating:
In the four years since then, the use of ultrasonic techniques have [sic] become so widespread that a controlled trial along the lines originally proposed would no longer be ethically possible.”
It was, apparently, “ethically possible” to expose almost every unborn child in the United Kingdom to a procedure whose safety had not been evaluated – and is still not properly evaluated more than forty years later.
In 1985 we were pressing the Department again. We told the Minister of our continued concern that there was still no evidence that routine ultrasound was medically effective, cost effective, and did not cause long-term damage. By now the RCOG had published their report on “Routine Ultrasound Examination in Pregnancyand we prepared a detailed critique of it for the Association for Improvements in the Maternity Services (Beech B et al., 1985). We said it was unscientific in its approach and it had been very selective in the research papers which were quoted. Our criticisms were validated by the British Journal of Obstetrics and Gynaecology (May1985) which said that “the scientific analysis did not show rigor which normally would be expected of its scientific committee.”When our criticisms were reported in the “New Scientist”(17thMay 1984) Professor Stuart Campbell dismissed them saying“they show how desperate they are to cause trouble.”
Over the years numerous animal studies have suggested possible hazards of ultrasound, the following is a small selection:
alterations in baby monkeys’ behaviour (Tarental AF et al., 1993),
a small but statistically significant number of neurons failing to acquire their proper positon and remain scattered within inappropriate cortical layers and/or in the subjacent white matter (Ang ES et al., 2006);
Short, intermediate and long-term memory impaired in chicks exposed to ultrasound before hatching (Scheider-Kolsky et al (2009),
alterationsand changes in bone mineral density (Md Dom S. 2012),
Mice exposed to diagnostic ultrasound in utero are less social and more active in social situations relative to controls (McClintic AM, 2013).
The animal studies have been consistently ignored or dismissed as not relevant to human babies. It was not until women began to purchase ‘Keepsake or Souvenir Videos’ that the medical profession issued a warning, but their words were carefully chosen:
B-mode ultrasound used for clinical reasons from conception to 10 weeks of gestation is safe and the benefits outweigh any theoretical risks. We are adopting a precautionary approach and are highlighting the small but possible risks to women so that they can make informed choices. We also emphasise that any healthcare professional involved in the use of ultrasound is aware of the safety principles of ultrasound. Dr Sadaf Ghaem-Maghami, Chair of the RCOG’s Scientific Advisory Committee, 3 Mar 2015.
In 1985 the FDA regulation limited ultrasound exposure to 46 mW/cm2 spatial peak intensity, but in 1992 increased this to a possible limit of 720mW/cm2, a fifteen times increase in output by ultrasound devices that incorporate an approved real-time output display in their design. (Miller D, 2008).
Unfortunately, the research shows that many healthcare professionals are not aware of the restrictions that should be in place. A questionnaire to doctors, sonographers and midwives found that only one third understood mechanical and thermal safety indices, fewer than a third understood where to find the safety indices on the screen and just over one in five (22%) knew how to adjust the energy output on their machine (Salvesen K, 2011).
Indeed, recent headline news informed us of new “beautiful” 3D images of fetuses in utero which can now be produced through ultrasound imaging andMRI scanning techniques. Although ostensibly developed to help plan for babies with heart defects; the news programmes described “amazing images”, as they showed the vulnerable foetus exposed to intense ultrasound exposure. Nowhere in the Radio 4 broadcast or the Ten o’clock News was there any mention of safety.
Jim West in his bibliography of 50 human studies undertaken by Chinese researchers highlights the findings from research papers involving 2,651 women. Because of China’s one baby policy many babies were aborted, but the Chinese researchers obtained agreement from the mothers to expose their babies to varying amounts and duration of ultrasound and then conduct examination of the babies’ brains post abortion. After the abortions the babies’ brains, kidneys, eyes or chorioamnion tissue were examined and electron microscopes used to visualise sub-cellular damage. The results are of considerable concern. It is clear from the research that the ultrasound exposure significantly affects the brain structure. Because there has been no research examining the long-term effects of ultrasound one can only speculate on the long term effects.
These studies would not have come to light were it not for the efforts of Jim West whose book ‘Diagnostic Ultrasound: A New Bibliography, Human Studies Conducted in Modern China reveals the evidence, and Sarah Pope whose article in ‘The Healthy Home Economist’ revealed the findings.
In 2000, Professor Ruo Feng, of the Institute of Acoustics, Nanjing University, recommended the following action:
Ultrasound should only be used for specific medical indications;
Ultrasound, if used, should strictly adhere to the smallest dose principle, that is the ultrasonic dose should be limited to that which achieves the necessary diagnostic information under the principle of using intensity as small as possible, the irradiation time as short as possible.
Commercial or educational fetal ultrasound imaging should be strictly eliminated. Ultrasound for the identification of fetal sex and fetal entertainment imaging should be strictly eliminated.
For the best early pregnancy [1st trimester], avoid ultrasound. If unavoidable, minimize ultrasound. Even later, during the 2nd or 3rd trimester, limited ultrasound to 3 to 5 minutes for sensitive areas, e.g. fetal brain, eyes, spinal cord, heart and other parts.
For every physician engaged in clinical ultrasound training, their training should include information on the biological effects of ultrasound and ultrasound diagnostic dose safety knowledge. (quoted in West J, 2015).
While acknowledging that ultrasound can be of value in specific instances we believe that women should be alerted to the risks so that they can make properly informed decisions about whether or not to expose their baby in utero and the long-term effects of ultrasound exposure should be investigated.
We look forward to hearing what action you intend taking.
Beverley A Lawrence Beech Jean Robinson
Ang ESBC Jr, Gluncic V, Duque A, Schafer ME and Rakic P (2006). Prenatal exposure to ultrasound waves impacts neuronal migration in mice. Proceedings of the National Academy of Sciences of the USA, 103 (34) 12903910; https://doi.org/10.1073/pnas.0605294103https://www.pnas.org/content/103/34/12903
Beech B A, Green M, Rodgers C and Squire J (1985). Commentary of the Report of the Royal College of Obstetricians and Gynaecologists Working Party on Routine Ultrasound Examination in Pregnancy. Association for Improvements in the Maternity Services.
McClintic A M, King B H, Webb S J and Mourad P D (2013). Mice exposed to diagnostic ultrasound in utero are less social and more active in social situations relative to controls, International Society for Ultrasound Research, Nov. 2013, https://doi.org/10.1002/aur.1349
Md. Dom S., Salikin M. S., Hassan H. F., Mohd Yusoff N (2012). The effect of B-mode diagnostic ultrasound exposure on rabbit foetal bone mineral density (BMD). Radiography18: 197–200. doi: 10.1016/j.radi.2011.11.011
Miller D (2008). Safety Assurance in obstetrical ultrasound, Semin Ultrasound CT MR, April, 29(2), p156-164.
Salvesen K, Lees C, Abramowicz J, Brezinka C, Ter Haar G, Maršál K(2011). Safe use of Doppler ultrasound during the 11 to 13+6 week scan: Is it possible?, Ultrasound in Obstetrics and Gynecology, 37, No6, p628.Schneider-Kolsky M E, Avobi Z, Lombardo P, Brown D, Kedang B and Gibbs M E (2009) Ultrasound exposure of the foetal chick brain: effects on learning and memory, International Journal of Developmental Neuroscience, Vol 27, Issue 7, Nov 2009, p677-683.
Tarantal AF et al. Evaluation of the bioeffects of prenatal ultrasound exposure in the Cynomolgus Macacque (Macaca fascicularis): III Developmental and Mematologic Studies, Teratology (1993), 47: p159-170
West J (2015). 50 human studies in utero, conducted in modern China indicate extreme risk for prenatal ultrasound. A new bibliography commentary, Library of Congress Control Number 2015944054. ISBN 978-1-941719-03-8,
West J (2017). Townsend Letter – The Examiner of Alternative Medicine. http://www.townsendletter.com/April2017/ultrasound0417.html