Ultrasound: high-frequency sound waves that travel at 10-20 million cycles per second. The pattern of echo waves results in a picture of tissue and bone.
Later, UK radiologist H.D. Meire, who had been performing pregnancy scans for 25 years, commented, “The casual observer may be forgiven for wondering why the sonography medical profession has become involved in the wholesale study of pregnant patients with machines emanating vastly different powers of one’s which isn’t shown to be harmless to obtain information which is not shown to be associated with a clinical value by operators who’re not certified as competent to perform the operations”.
Ultrasound Routine prenatal ultrasound (RPU) actually detects only between 17 and 85 % from the One in 50 babies who’ve major abnormalities at birth. RPU can identify a low-lying placenta (placenta previa). However, 19 of 20 ladies who have placenta previa detected with an early scan will be needlessly worried: the placenta will effectively progress without causing problems at the birth. Furthermore, detection of placenta previa by RPU is not found to be safer than detection in labor.
The American sonography College of Obstetricians has figured “in a population of ladies with low-risk pregnancies, neither a decrease in perinatal morbidity and mortality nor less rate of unnecessary interventions should be expected from routine diagnostic ultrasound. Thus ultrasound ought to be performed for specific indications in low-risk pregnancy.
Results of ultrasound include cavitation, a process wherein the small pockets of gas that exist within mammalian tissue vibrate after which collapse. Within this situation “…temperatures of many thousands of degrees Celsius within the gas create a wide range of chemicals, some of which are potentially toxic. These violent processes might be made by microsecond pulses of the kind that are utilized in medical diagnosis.” (American Institute of Ultrasound Medicine Bioeffects Report 1988). The significance of cavitation in human tissue is unknown.
Studies have suggested that these effects are of real concern in living tissues:
* Cell abnormalities brought on by contact with ultrasound were seen to persist for several generations.
* In newborn rats (similar stage of development as human fetuses at 4 to 5 months in utero), ultrasound can damage the myelin that covers nerves.
* Exposing mice to dosages usual for obstetric ultrasound cased a 22% decrease in the speed of cell division and doubling from the rate of aptosis (programmed cell death), in the cells of the small intestine.
* Two long-term randomized controlled trials comparing exposed and unexposed childrens’ development at eight to nine years old found no measurable effect from ultrasound. However, the authors comment that intensities used today are lots of times higher than there were in 1979 and 1981.
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