Ultrasound dangers OF 2- and 3-D images of fetuses in the womb

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Ultrasound dangers http://findarticles.com/p/articles/mi_m0816/is_2_23/ai_n19328634Obstetricians use ultrasound waves to generate 2- and 3-D images of fetuses in the womb, and these images allow them to answer important medical questions. Is the fetus in the correct location? How many fetuses are in the womb (one or several)? Are there birth defects, such as kidney or nervous system abnormalities?In the past few years, commercial facilities have started to offer ultrasounds not for medical use but for entertainment, for parents to collect pictures and videos of the baby developing in the womb. New research suggests, however, that prolonged exposure to ultrasound waves while in the womb can impair normal brain development. How does a normal brain develop? The following four steps summarize normal brain development:1. Brain cells divide.2. Many of the newly divided brain cells migrate (move and crawl) to new locations within the nervous system.3. Once a brain cell has arrived at the new location, movement stops and the brain cell forms connections with neighboring brain cells.4. Only brain cells with strong connections between other brain cells survive. Brain cells with weak connections die.Would exposure to ultrasound waves while developing in the womb disrupt normal brain development? To answer this question, researchers treated pregnant mice with ultrasound waves for 5,15, 30, 60, 210, or 420 minutes. A few days after the pregnant mice gave birth to their offspring, researchers analyzed the brains of the baby mice. While the brains of mice exposed to ultrasound waves for brief lengths of time (5 and 15 minutes) were normal, the brains of mice exposed to ultrasound waves for longer lengths of time (30, 60, 210, or 420 minutes) were not normal. Researchers found that when mice were exposed to ultrasound waves for long time periods, some brain cells failed to migrate to the correct location within the brain. Further, the longer the exposure to ultrasound waves, the fewer brain cells migrated to the correct location.What are the implications for disruption of brain cell migration? Prior research compared epileptic, schizophrenic, and even autistic brains to normal (non-disease state) brains. In some types of epilepsy, some brain cells never migrated. Compared to normal brains, many schizophrenic and autistic brains had abnormalities in brain cell organization and arrangement. Based on these observations, researchers suggested that disruption of brain cell migration is the underlying cause of disorders such as epilepsy, autopsy, and schizophrenia.Caution should be used before over-interpreting the results of these studies. During prenatal development, human brain cells migrate for 18 weeks while mice brain cells migrate for one week. Therefore, 30 minutes may not be as detrimental to humans given the longer time period for brain cell migration. Finally, the only way to demonstrate that ultrasound waves given in these time intervals may result in abnormalities such as epilepsy would be to conduct similar experiments with human subjects. However, as such experiments are unethical, mice are used as models.In 2004, the FDA issued a warning against the use of ultrasound waves for non-medical purposes. These new studies further support the FDA's warning. Outside the medical office, babies in the womb should not be exposed to additional ultrasound waves merely for the collection of photos, as increasing the amount of time that the developing baby is exposed to ultrasound waves risks disrupting normal brain development.Susan Kralian, PhD, is a former college professor, high school teacher, laboratory technician, and Peace Corps volunteer. She lives and works in New York, NY.COPYRIGHT 2007 Pediatrics for Parents, Inc.COPYRIGHT 2008 Gale, Cengage Learning12Next »Find Research Guides for: AbortionADHDAIDSAlternative EnergyAlternative MedicineCancerCapital PunishmentCloningHate CrimeCryonicsDrug AbuseEating DisordersGay IssuesGlobal WarmingHolidaysImmigrationMedicalMen's HealthMental HealthReal EstateStem CellsWomen's HealthFind Featured Titles for: Arts